FOOD CONTAMINATION MONITORING AND FOOD-BORNE DISEASE SURVEILLANCE AT NATIONAL LEVEL

(Paper prepared by Lo Fo Wong DMA^[19], Andersen JK^[20], Nørrung B¹⁹, Wegener HC²⁰)

Abstract

Cost-efficient monitoring of food contamination and surveillance of food-borne diseases requires a coordinated multidisciplinary approach with the participation of stakeholders from all sectors of the "farm-to-fork" continuum including the public health sector. To facilitate communication and coordination, establishment of a coordinating body with the participation of relevant stakeholders is recommended. Furthermore, relevant surveillance data from all stages in the food production chain and from the surveillance of human disease should be continuously collected and analyzed to evaluate trends and sources of food-borne disease. The establishment of a dedicated multidisciplinary surveillance unit involving epidemiological and microbiological expertise from all sectors can facilitate this type of coherent data analysis and feed back. Systems such as these can be operated at the national, regional and global level.

Monitoring And Surveillance as Tools in Food Safety Assurance

In order to address and manage food safety, it is imperative to have knowledge on the current situation and trends with regard to the occurrence and spread of human pathogens in the food production chain. This knowledge needs to be updated continuously so that appropriate responses can be prepared. Activities involved in such a system are gathered under the terms 'monitoring' and 'surveillance' (Fig. 1). Monitoring can be defined as: "the performance and analysis of routine measurements, aimed at detecting changes in the environment or health status of populations". Surveillance can be defined as: "the ongoing systematic collection, collation, analysis and interpretation of data, followed by the dissemination of information to all those involved so that directed actions may be taken" (WHO/CDS/CSR).

Surveillance refers to a specific extension of monitoring where obtained information is utilized and measures are taken if certain threshold values related to disease status have been passed (Noordhuizen and Dufour, 1997). The main objectives of surveillance are outbreak detection, monitoring trends in endemic disease, evaluating interventions, and monitoring programme performance and progress towards a predetermined control objective. However, surveillance is not merely a routine measure of the current situation (as opposed to monitoring), but a basis for giving qualified feed-back to producers, tracing back contamination to its origin, pin-pointing critical (control) points during production and initializing targeted action.

Figure 1. Graphic presentation illustrating the relation between monitoring and surveillance.

There are various levels of intensity and coordination in surveillance systems. Surveillance can be active or passive, general or sentinel, continuous or intermittent, disjointed or integrated. In general, the intensity of surveillance is a product of social (i.e. priority of disease, societal impact), practical (i.e. availability of epidemiological knowledge) and financial parameters.

The Need for a National Approach

Pathogenic microorganisms can enter the food chain at any point, from livestock feed, via the on-farm production site, at the slaughterhouse or packing plant, in manufacturing, processing and retailing of food, through catering and home preparation. Since there are numerous possible routes for transmission of pathogens throughout production, isolated actions (e.g. decontamination of animal feed) will in most cases not ensure lasting consumer protection. In order to effectively manage the problem of food-borne disease, measures should be considered at all levels of production. This requires a coordinated surveillance and response effort from all major stakeholders in food safety.

The food industry is responsible for the quality and the safety of their products and is therefore a major stakeholder in food safety. Production may be monitored through, for example, certification programmes, process control schemes or HACCP (Hazard Analysis Critical Control Points) based control programmes. These control activities generate data that can constitute an important contribution to national surveillance programmes. Also, in an outbreak investigation, additional sampling may be required to trace-back human infection to the point of contamination in the food-production chain. Close cooperation between the private and public sector is therefore imperative.

In general, the main stakeholders in food safety representing the government are the Ministries of Health and the Ministries of Agriculture/Food. Under them are agencies that are responsible for the legislative, technical and practical implementation of food safety programmes, and each agency often has a dedicated reference laboratory associated with it. The access to surveillance data often goes through these laboratories. These two or possibly three organizational structures often run independent of each other. In order to get a comprehensive view of the national food safety status, the two Ministries and their respective agencies and reference laboratories should work closely together.

Figure 2. Schematic presentation of the collection, collation, analysis and interpretation of surveillance data and the subsequent dissemination of information to all the major stakeholders in food safety

Finally, other stakeholders of food safety are the non-governmental organizations. They may represent consumers, food industry workers or the environmentalists. Although these organizations seldom are directly involved in the generation of data, they can influence the launching of food safety initiatives and serve as a driving force behind initiation of surveillance efforts.

The main challenge is to develop structures that ensure the systematic collection, collation, analysis and interpretation of surveillance data and communication to all public and private stakeholders involved (Fig. 2). For this purpose, one or more coordinating bodies or steering committees with representatives of all stakeholders may be formed. The integration of all surveillance data from farm-to-fork in a coherent analysis and subsequent interpretation may be the task of a specialized multidisciplinary research unit, which reports to the relevant coordinating bodies or steering committees. The evaluation by these committees can then lead to a coordinated response.

Integration of surveillance activities to the national level facilitates optimization and cost efficiency in the generation and utilization of surveillance data. The challenge is to optimize the sensitivity of the surveillance system while minimizing the costs. For example:

• Integration of surveillance components within and between links of a production chain, e.g. to investigate possible associations between the levels of food-borne pathogens in food animals and in food products at retail;

• Integration of different surveillance programmes of the same production animal, e.g. using the same serum samples for the detection of antibodies against both Salmonella and PRRS;

• Integration of different surveillance programmes for different production animals, e.g. to estimate the relative contribution of the main reservoirs to the total number of human cases of food-borne illness;

• Integration of national surveillance programmes to rapidly recognize and report international outbreaks, e.g. EnterNet, OzFoodNet and Global SalmSurv.

The integration of food-borne disease surveillance activities can be achieved through: 1) communication, 2) collaboration, 3) coordination and 4) central storage of data. Communication between major stakeholders can be maintained during regular meetings and direct, informal contact between veterinary and public health workers in key-positions. Collaboration consists mainly of the routine exchange of data and participation in outbreak investigation and response. Control activities and the sharing of information need to be coordinated, within and between programmes. Managing a central database containing all surveillance data allows for coherent analyses of the relation between food-borne-pathogen reservoirs and disease in time and space. These four components ensure the optimal use of data that already is being generated.

The Role of National Monitoring and Surveillance in Risk Analysis

Though the main purpose of surveillance is disease control, surveillance data is widely used as part of a risk analysis framework (i.e. in risk assessment and risk management) (Fig. 3). Surveillance programme outcome allows for the detection of events and developments that require a detailed evaluation of the situation (i.e. risk evaluation). By incorporating results from all pertinent lines of investigation (e.g. monitoring and surveillance programmes, outbreak investigations, surveys, analytical studies), risk assessors can develop risk models that are used to evaluate alternative intervention and control strategies.

Figure 3. The cycle of public health protection, illustrating the role of surveillance in supporting risk assessment, risk management and formulating new research efforts.

Results from risk assessments provide decision-support to risk managers. The options provided by the risk assessment are evaluated together with social and financial factors (i.e. option assessment). Subsequently, the effect of risk management actions can be monitored through surveillance (i.e. monitoring and review).

Salmonella Surveillance in Denmark - An Example of an Integrated Approach

In Denmark, the successful implementation of a number of surveillance and control programmes can be accredited to the close cooperation between public sector and private industry (Wegener et al., 2003). The authorities have delegated the responsibility for technical coordination of the programmes to committees with representatives from the industry, government bodies and science. In the planning and implementation of programmes, there has been a close involvement of microbiologists and epidemiologists. In addition, there is a very close collaboration between medical and veterinary epidemiologists and microbiologists in monitoring the effect of the programmes on the incidence of human infection.

To initiate and generate the basis for targeted action, the Danish Zoonosis Centre was established in January 1994. The Zoonosis Centre is an epidemiological surveillance and research unit recently moved under the newly formed Ministry of Family and Consumer Affairs (previously the Ministry of Food, Agriculture and Fisheries). The Zoonosis Centre collects all data from all national surveillance and control programmes on zoonoses and conducts an ongoing analysis of the national zoonosis situation from farm-to-fork, including the identification of outbreaks, the assessment of sources of human food-borne disease as well as basic epidemiological research.

A report on trends and sources of zoonoses in Denmark is published annually by the Zoonosis Centre (Fig. 4), in hard copy and on the Internet (http://www.dfvf.dk/Default.asp?ID=9606)

Figure 4. Annual Report on Zoonoses in Denmark with the estimated attribution of major animal reservoirs to human salmonellosis

The report includes an annual account of major sources of food-borne salmonellosis based on surveillance, as well as an overview of the trends in the estimated attribution of these sources to human infection since 1988. Detailed knowledge of the distribution of Salmonella subtypes in all relevant food animals and food types, generated through intensive and continuous monitoring, is an essential prerequisite for the analysis (Hald et al., 2004).

The Zoonosis Centre conducts quarterly meetings where the current status of the human incidence and control programmes on food-borne zoonoses is communicated to relevant stakeholders. The stakeholders are organized in three so-called "coordination-groups". The first coordination-group also serves as a board for the Zoonosis Centre. It has representatives of all government agencies and institutions involved in monitoring and control of food and water borne infections. This group includes; Statens Serum Institut, the Danish Veterinary and Food Administration, the Danish Plant Directorate, the Danish Institute for Food and Veterinary Research, the National Board of Health, the Danish Environmental Protection Agency and the Royal Veterinary and Agricultural University. The second coordination-group represents the producers; the Danish Bacon and Meat Council, the Danish Meat and Livestock Board, the Danish Dairy Board, the Federation of Egg Producers, the Federation of Slaughter Poultry Producers and the National Board of Agricultural Producers. The third coordination-group consists of "other interested parties", such as the National Consumers Board, the National Retailers Board, the Union of Food Industry Workers, the Danish Industry Board and the Federation of Hotel and Restaurant Owners. The Centre is also responsible for communication to the general public and the media through press-releases, printed reports, publications, and a website.

A number of other countries have in recent years established similar or related structures to improve surveillance and facilitate communication and coordination. These countries include Finland, Germany, Ireland, Norway, Sweden, United Kingdom, and many more.

Food Contamination Monitoring at the National Level in Denmark

The organization of the Danish food control system has been changed over the last 5 years. Previously, food control at the retail level was carried out by a large number of local food control units that referred to local authorities. Apart from the fact that the local control administration was not cost efficient, the organization was flawed by heterogeneity in several important aspects, such as the evaluation of microbiological results and in prioritizing control activities. Also the decentralized organization of these control units created problems when dealing with nationwide establishments. Re-organization has put the regional laboratories under direct supervision of the national food authority, instead of the local administrations. The control of food production from farm-to-fork was hereby joined in one body, under direct governmental jurisdiction. Furthermore, in the retail sector there has been a movement towards increased own-control in recent years. The implementation of HACCP in the producers' own control programmes has reduced the degree of involvement of the authorities in the organization of food control systems.

Currently, the inspection and control is more of an auditing nature with emphasis on generating general knowledge on the contamination on food items, instead of specific knowledge on the general hygiene in establishments, i.e. microbiological testing is focused on collecting data on the occurrence of specific pathogens in various food commodities as compared to earlier where testing for indicator organisms for monitoring of the general hygiene was very common. Thus, the food control in the retail sector is aiming more at collecting information needed to improve human health. Fewer samples are taken on a routine basis, and more samples are taken to gather information on specific problems or to obtain information needed to perform activities within a risk analysis framework (Fig. 3).

Elucidation of specific problems and gathering of information for the use in Risk Analysis are performed in so-called "Centrally coordinated projects". The shift in focus is illustrated by the fact that the number of samples collected for surveillance of general hygiene in retail shops has decreased from 79,000 in 1998 to 23,000 in 2003. In the same period the number of samples collected for specific projects has increased from 3000 in 1998 to 17,000 in 2003.

These projects are carried out to collect information on pathogen/commodity combinations needed in risk analysis. This knowledge may be needed in Risk Assessment (i.e. for gathering data on Exposure Assessment) as well as in Risk Management (i.e. for the Monitoring and Review of the impact of Risk Management options. The centrally co-coordinated projects performed in 2003 are presented in Table 1.

Table 1. Centrally co-coordinated microbiological projects performed in Denmark in 2003, with the number of samples investigated.

The content of these "Centrally coordinated projects" are decided each year through a process involving the central and regional authorities as well as the Danish Institute for Food and Veterinary Research.

Concluding Remarks

The detection of changes of food-borne diseases patterns and variations in the contamination in the food production process are an absolute necessity for the monitoring and continuous improvement of food quality and safety. These programmes need to be sensitive, sensible and cost efficient. Food contamination monitoring and food-borne disease surveillance at national level provides a timely and comprehensive overview of the veterinary and public health status of a nation. The integration of food-borne disease surveillance has the goal to gather all national surveillance activities in a common public service that carries out many functions using similar structures, processes and personnel. The infrastructure of an established surveillance programme in one area may serve as a framework for strengthening other surveillance activities. Though some food-borne diseases may have specific information needs, requiring specialized systems, there may be the potential for synergy and the sharing of common resources.

References

Hald T, Vose D, Wegener HC, Koupeev T.A Bayesian approach to quantify the contribution of animal-food sources to human Salmonellosis.Risk Anal. 2004; 24(1):251-265.

Noordhuizen JPTM, Dufour B, 1997. Monitoring and Surveillance Systems (MOSS), Design and Operationalization. In: Noordhuizen JPTM, Frankena K, van der Hoofd CM, Graat EAM (eds.), Application of Quantitative Methods in Veterinary Epidemiology. Wageningen Pers, Wageningen, 1997, pp. 377-396.

Wegener HC, Hald T, Lo Fo Wong DM, Madsen M, Korsgaard H, et al. 2003. Salmonella control programmes in Denmark. Emerg Infect Dis. 2003 Jul; 9(7):774-780.

WHO. Communicable Disease Surveillance and Response (CSR), slideshow on 'Principles of Surveillance'. http://www.who.int/emc/surveill/index.html.

INTERNATIONAL COOPERATION ON FOOD CONTAMINATION AND FOODBORNE DISEASE SURVEILLANCE

(Prepared by the United States of America)

Introduction

A primary challenge in the 21st Century is to minimize food safety risk to consumers as the scientific complexity of food grows, and as trade, regulation, new health threats, and consumption patterns continue to change, particularly with respect to the global food supply. The World Health Organization (WHO) reports that surveillance of food-borne diseases is becoming an increasingly high priority in the public health agenda in many countries. Such surveillance helps estimate the burden of food-borne diseases, assess its relative impact on health and economics, evaluate disease prevention and control programmes, and allows for rapid detection of and response to outbreaks. It is also a major source of information for conducting risk assessment, and more broadly for risk management and communication. Food-borne disease surveillance should be integrated with food monitoring data and data from food animals along the entire feed-food chain. Integrating such data would result in robust surveillance information and allow appropriate priority setting and public health interventions. Intersectoral, inter-institutional, and international collaboration are of paramount importance. National surveillance is of varying intensity depending on the country and region on the globe. Additionally, methods used are not necessarily uniform, making data interpretation difficult. Organizations such as the WHO, the World Organization for Animal Health (OIE), and the Food and Agriculture Organization of the United Nations (FAO), are working to improve international surveillance.

With respect to the United States, the U.S. Department of Health and Human Services' (HHS) Centers for Disease Control and Prevention (HHS/CDC), in close collaboration with State and Territorial Departments of Health, are responsible for conducting human disease surveillance. The U.S. Department of Agriculture's (USDA) Food Safety and Inspection Service (FSIS), as well as the HHS' Food and Drug Administration (FDA), closely monitor this disease surveillance through a variety of human and technological liaison activities described below. FSIS and HHS/FDA react to episodes of food-borne disease based on epidemiological information from HHS/CDC or other state and local health authorities linking illnesses to food products. However, both FSIS and HHS/FDA would benefit from better coordination, both nationally and internationally, linking what we see in terms of surveillance with what we observe with foods.

Existing Surveillance Systems and the Development of International Cooperation

United States Continental Alert and Monitoring Systems

HHS/CDC maintains routine national surveillance for individual cases of food-borne infections that depend on regular reporting from state public health departments. These nationally notifiable disease reporting systems collect limited standard information, help track trends in those infections, and alert local, state and national health authorities to potential outbreaks. Serotyping clinical isolates of Salmonella at state public health laboratories is a critical part of this surveillance. In addition, HHS/CDC also maintains a reporting system for food-borne outbreaks that are investigated and reported by local and state health departments. This is a web-based reporting system called the Electronic Food-borne Outbreak Reporting System (EFORS). EFORS collects standardized information on more than 1200 reports of outbreaks each year.

HHS/CDC also conducts active surveillance for food-borne disease through a collaborative active surveillance network called FoodNet. The Food-borne Diseases Active Surveillance Network (FoodNet) is the principal food-borne disease component of HHS/CDC's Emerging Infections Programme (EIP). FoodNet is a collaborative project of the HHS/CDC, 10 EIP sites (California, Colorado, Connecticut, Georgia, New York, Maryland, Minnesota, Oregon, Tennessee and New Mexico), USDA, and HHS/FDA. The project consists of active surveillance of food-borne diseases and related epidemiologic studies designed to help public health officials better understand the epidemiology of food-borne diseases in the United States. Food-borne diseases include infections caused by bacteria such as Salmonella, Shigella, Campylobacter, Escherichia coli O157:H7, Listeria monocytogenes, Yersinia enterocolitica, and Vibrio, and parasites such as Cryptosporidium and Cyclospora. In 1995, FoodNet surveillance began in five locations: California, Connecticut, Georgia, Minnesota, and Oregon. Each year, the surveillance area, or catchment, has expanded, with the inclusion of additional counties or additional sites (New York and Maryland in 1998, Tennessee in 2000, Colorado in 2001 and New Mexico in 2004). The total population of the 2003 bacterial catchment is 37.6 million persons, or 13.8% of the United States population. FoodNet provides a network for responding to new and emerging food-borne diseases of national importance, monitoring the burden of food-borne diseases, and identifying the sources of specific food-borne diseases. FoodNet provides accurate and detailed surveillance information about those infections for which surveillance is variable or non-existent from state to state. FSIS and FDA's Center for Food Safety and Applied Nutrition (CFSAN) also participate in the FoodNet surveillance activities. For more information see www.cdc.gov/foodnet

PulseNet, the national molecular subtyping network for food-borne disease surveillance, was established in 1996 by HHS/CDC and several state health department laboratories to facilitate subtyping bacterial food-borne pathogens for epidemiologic purposes. PulseNet reached full national participation in 2001. Public health laboratories in all 50 states routinely determine the molecular fingerprints of Escherichia coli O157:H7, Listeria monocytogenes, and regularly subtype common serotypes of Salmonella; standard protocols have also been developed for subtyping a growing number of other food-borne pathogens. Food regulatory laboratories at HHS/FDA and FSIS also participate, and HHS/CDC maintains the national database of patterns. Rapid electronic comparison of strain patterns in state and national databases provides early detection of clusters of related infections, guiding investigations, and verifying control. PulseNet identifies potential outbreaks that otherwise would have been missed, particularly those that are widely dispersed. Identifying and investigating such outbreaks can identify system problems in food safety, so that they can be corrected. For example, with the regular use of PulseNet, the frequency of detected outbreaks of listeriosis in the United States has increased from one every five years to two per year, focusing attention on critical points of control within the food safety system. For more information see www.cdc.gov/pulsenet.

In collaboration with WHO, the HHS/CDC helped to establish the International Collaboration on Food-borne Diseases "Burden of Illness Studies" Network in March 2004, as a means of establishing communications and collaboration among nations developing burden of illness studies, specifically with respect to acute gastrointestinal illness and food-borne disease.

Food-borne outbreak investigations are a critical part of the food safety system. New and recurrent food-borne hazards can be rapidly identified by investigation of food-borne outbreaks. Careful investigation of an outbreak, including tracing the food from farm to table and reconstructing the means of contamination, is critical to move the food safety agenda forward when new hazards emerge. Most outbreaks are investigated and controlled by local and state health departments. HHS/CDC routinely consults with the state health departments as they investigate outbreaks, launches emergency field investigations to assist them in large, complex or unusual outbreaks, collaborates with HHS/FDA and USDA/FSIS on the traceback of implicated food items to their origins, and coordinates efforts to improve outbreak detection and investigation methods.

U.S. federal agencies, state/county officials, foreign governments, law enforcement, health professionals, industry, or news media may issue an alert or notification. Alerts/notifications are related to problems with products that may pose a risk to the public. Information is shared within legal constraints, and information received from other organizations is used to improve analysis and respond to problems. U.S. agencies call upon the capabilities of their various stakeholder communities-regulators, public health partners, industry, and consumers-to generate effective solutions to complex food safety challenges. HHS/FDA and USDA rapidly coordinate responses to contain a problem and remove products from commerce to protect the public's health.

HHS/FDA's Emergency Operations Center (EOC) tracks food-borne outbreaks in the United States. If an HHS/FDA-regulated product is identified in a food-borne illness, EOC coordinates agency-wide responses, including sample collection and analysis, interpretation of disease-related data, and trace back of implicated products. HHS/FDA also has various educational efforts with State and local regulatory authorities promoting food-borne illness investigations. Well-trained personnel enhance surveillance, and FDA relies strongly on State and local authorities for quality surveillance information. HHS/FDA also has a Trilateral Agreement for product notifications with Canada and Mexico. In addition, HHS/FDA monitors various electronic and media sources, such as ProMed, which may provide signs of emerging issues. EOC conveys proper alerts through various mechanisms to respond effectively to these situations, as needed.

FSIS relies on a cadre of Public Health and Epidemiology Liaison officers located in regionally based offices (Atlanta and Omaha) who maintain active and open communications with State and Territorial health officials, and are USDA/FSIS' first point of contact for reports of illness that may be associated with meat, poultry or egg products. There is a 24-hour toll-free number for public health partners to call which routes the caller to the appropriate officer. Additionally, USDA/FSIS has a liaison officer assigned to the HHS/CDC, enabling USDA/FSIS to receive the earliest warning on food-borne illnesses that may involve regulated products.

HHS/FDA and FSIS officials receive alerts from HHS/CDC's Epi-X electronic alert system. Epi-X is a web-based communications system operated by HHS/CDC. Distribution of information through the Epi-X network is to promote rapid communications of recent outbreaks and other health events among local, state, and federal health officials. Epi-X carries reports of disease events outside, as well as inside, the United States. This dissemination of international health information promotes further surveillance of these conditions in the United States, as well as follow-up collaborations with foreign authorities dealing with these health events.

On an emergency basis, HHS/FDA maintains after hours phone contact numbers for all 50 States, and shares information through regularly scheduled conference calls with the States and ad-hoc calls. Additionally, HHS/FDA has the S.A.F.E.S (State Advisory FAX/Email system) communication system, which allows HHS/FDA to broadcast FAX and email information to all 50 states on demand. It is regularly used to disseminate information by the Agency. State agencies that may participate in calls or receive information include Departments of Health, Agriculture, Boards of Pharmacy, Environmental Health, Poison Control Centers, Fish and Wildlife, and State Veterinarians.

HHS/FDA's Office of International Programmes and FSIS's Office of International Affairs disseminate food safety information to foreign counterpart food regulatory authorities in other countries, as appropriate. For example, for a food product that is recalled because there is a reasonable probability that use of or exposure to the product will cause serious health consequences or death (referred to as Class I), and is exported, notification will be provided to the counterpart authorities.

The HHS Office of Global Health Affairs coordinates the U.S. work on the International Health Regulations (IHRs), which will include a set of internationally reportable diseases, including food-borne diseases. This involves a multi-agency effort that includes, not only HHS agencies, but also State, USTR, and USDA agencies. HHS/FDA has actively participated in this endeavour for a number of years by reviewing documents and providing comments as appropriate. More recently, FSIS and the USDA's Animal and Plant Health Inspection Service have also participated in the development of the IHRsThe Electronic Laboratory Exchange Network (eLEXNET) is a seamless, integrated, web-based data exchange system for food testing information that allows multiple agencies engaged in food safety activities to compare, communicate, and coordinate findings of laboratory analyses. eLEXNET is funded by HHS/FDA and supported by USDA and the Department of Defence (DOD). It enables health officials to assess risks and analyze trends, and it provides the necessary infrastructure for an early-warning system that identifies potentially hazardous foods. At present, there are 108 laboratories representing 49 states that are part of the eLEXNET systems with 62 laboratories actively submitting data. We are continuing to increase the number of participating laboratories.

The National Antimicrobial Resistance Monitoring System (NARMS) is an example of a well-coordinated surveillance programme among HHS/FDA, HHS/CDC, and USDA. NARMS monitors antibiotic resistance of select food-borne pathogens isolated from clinical settings (both human and animal) and the antibiotic resistance of isolates from foods. The system was initiated in 1996 in response to public health concerns associated with the approval of fluoroquinolone products for use in poultry. NARMS monitors changes in susceptibilities to 17 antimicrobial drugs of zoonotic enteric pathogens from human and animal clinical specimens, from healthy farm animals, from carcasses of food-producing animals at slaughter, and from isolates from samples of retail foods. The system includes a veterinary arm, a human arm, and a retail food monitoring arm.

HHS/FDA operates two post-marketing surveillance systems, the FDA Consumer Complaint System and the CFSAN Adverse Event Surveillance System (CAERS). The Consumer Complaint System monitors complaints from consumers and industry related to HHS/FDA-regulated products already in distribution, and can capture if there is a reported illness, injury, or alleged tampering related to the product.

FSIS has a Consumer Complaint Monitoring System (CCMS) managed by nurses who receive and triage each complaint about USDA/FSIS-regulated products, coordinating the investigation of those complaints that allege illness or injury. The CCMS investigations have led to recognition of outbreaks, voluntary recalls of adulterated products, and changes to specifications of school lunch products. This system is currently undergoing an enhancement which will allow early recognition of complaint patterns that may indicate unusual or intentional events.

Finally, FSIS monitors the occurrence of food-borne pathogens through a variety of sampling and testing programmes developed as verification of a food-producing establishment's Hazard Analysis and Critical Control Point/Pathogen Reduction plan. As such it is also a surveillance system, allowing FSIS to react to the presence of pathogens considered adulterants with the appropriate public health regulatory response, as well as to provide a rough estimate of the prevalence of specific pathogens on particular products.

Timely alerts via current notification processes are needed. Effective exchange of information is difficult when countries do not carry out the same methods and procedures or do not use the same set of standards. Many non-industrialized countries lack the resources to conduct meaningful surveillance, and even the countries that undertake surveillance may be using different methods and have different standards. These countries need trained staff in government, as well as adequately staffed and equipped laboratories and trained health care professionals, to identify and report diseases.

Establishing consistent laboratory methodologies, laboratory training, emergency preparedness training and procedures, database development, further assistance for developing countries, and strengthened communication networks are key strategies to advance the status of international food-borne disease surveillance. Identifying and exchanging specific contact information for specific products with other countries and developing agreements to cross-train with pertinent foreign officials would improve international information exchange. Some countries could also provide training, equipment, and technical support to international organizations, as well as to individual countries.

Surveillance of food-borne diseases should be given a high priority in the development of a food safety infrastructure. Building capacity for public health laboratories to conduct laboratory-based surveillance and to conduct epidemiologically-based surveillance are important global public health objectives. The needs of developing countries should be particularly considered. There is a need to be proactive in establishing one or more sentinel sites for food-borne disease in developing countries. There is also a need to develop and coordinate a global approach to strengthen surveillance at national, regional, and international levels.

Current surveillance is dependent upon physicians and clinical laboratories reporting illness and specific diagnosed infections. Thus, an improvement would be increasing the capacity of laboratories to identify specific pathogens and developing mechanisms to facilitate reporting of specific diseases. The ongoing support of interagency collaboration, international surveillance, and scientific research is crucial in preparing the international community to deal with food-borne disease in the global market place.

Food-borne disease surveillance within individual countries is important to track and to monitor domestic food-borne threats to public health. Existing national/regional systems such as that of the HHS/CDC, the European EnterNet, and that of the European Rapid Alert System for Food and Feed (see below) are examples of systems that may have applicability internationally. Collected information, including active and passive reporting from sub-jurisdictions (e.g., state and local public health officials), forms the basis of such systems and, when communicated to other countries, preferably though an international portal, is critical to global monitoring and surveillance. Within individual countries, the surveillance arm of government must coordinate with the regulatory arm of government to enforce food safety standards. These internal food safety networks support global surveillance, communication, and coordination. The current structure for international/regional food-borne disease surveillance includes both formal and informal relationships between and among countries. Formal programmes include Global Salm-Surv (a global network of laboratories and individuals involved in capacity building for surveillance, isolation, identification, and antimicrobial resistance testing of Salmonella) and the European Commission Health and Consumer Protection weekly reports from the Rapid Alert System for Food and Feed (RASFF). One goal of RASFF is to provide individual control authorities with an effective tool for exchanging information on food safety measures. Yet, formal international food-borne disease surveillance communication is limited. Much of what is shared has been dependent upon relationships that people at various agencies developed over the years with colleagues in other countries. WHO's new INFOSAN initiative (see below) should enhance information sharing significantly.

Efforts are emerging to strengthen international food-borne disease surveillance. HHS/CDC works with other countries to assist in developing their version of FoodNet, such as OZFoodNet (Australia's programme). In addition, a meeting (co-chaired by HHS/CDC and WHO) at the last international Conference on Emerging Infectious Diseases focused on the global effort to develop better food-borne disease reporting. There is a more general WHO disease surveillance programme called Communicable Disease Surveillance and Response, a data mining software developed by the Canadians. A number of international links can also be found at www.foodsafety.gov or http://omni.ac.uk/browse/mesh/C0012652L0012652.html. Another international electronic tool for food-borne disease information is ProMed, which reports on international health issues multiple times a day. Below are more details on some of the specific international collaborative efforts.

Strategies for Advancing International Cooperation of Foodborne Disease Surveillance

HHS/CDC International Collaborative Efforts

Collaborative efforts undertaken by HHS/CDC to foster international dissemination of food-borne infectious diseases information include:

Examples of International/Regional Cooperation

Global Salm-Surv

Global Salm-Surv is part of WHO's effort to strengthen the capacities of its Member States in the surveillance and control of major food-borne diseases and to contribute to the global effort of containment of antimicrobial resistance in food-borne pathogens. Since 2000, institutions and individuals in human health, veterinary, and food-related disciplines have participated in Salm-Surv activities, such as regional trainings for microbiologists and epidemiologists, external quality assurance and reference testing, an electronic discussion group, and a web-based databank containing an annual summary of laboratories. Over the next five years, Global Salm-Surv plans to improve its regional coverage with new training courses in Central Asia, Eastern and Southern Africa, Brazil, and Europe, encourage participation in the External Quality Assurance System and in Focused Regional or National Projects, expand to other food-borne pathogens (Campylobacter), produce training manuals in microbiology and epidemiology, and establish regional centers. For more information see: http://www.who.int/salmsurv/en/.

PulseNet International

PulseNet is HHS/CDC's highly successful DNA "fingerprinting" network for detecting food-borne bacterial disease clusters and assisting in outbreak investigations in North America. Over the past 4 years, PulseNet USA has developed a close working relationship and partnership with Health Canada in the formation of PulseNet Canada. PulseNet Canada shares its data with PulseNet USA on a real-time basis. This has facilitated early interventions in food-borne outbreaks in terms of investigative procedures and public health prevention strategies, thus preventing additional illnesses and possibly saving lives. HHS/CDC is now in the process of facilitating the replication of the PulseNet concept internationally.

A consortium of European scientists headed by the Statens Serum Institut, Copenhagen, Denmark, is working towards the establishment of PulseNet Europe. A feasibility study of PulseNet Europe was completed for three food-borne pathogens (Shiga-toxin producing E. coli, Salmonella, and Listeria monocytogenes). The results of this study were presented and discussed at a workshop held in Paris, France on 16 June 2003. PulseNet Europe was successful in obtaining funding from the European Union for 2005.

HHS/CDC, in partnership with the U.S. Association of Public Health Laboratories (APHL), organized a meeting in Honolulu, HI on 12 and 13 December 2002 to explore the possibility of setting up a PulseNet-compatible network in the Asia Pacific region. Fourteen participants from public health laboratories in12 countries/areas in the region attended the meeting. Through interactive brainstorming sessions, the benefits and challenges of forming PulseNet Asia Pacific were discussed, an action plan for the establishment of the network was developed, and a Steering Committee for this network was formed at this meeting. After the Honolulu meeting, several individual countries/areas have worked within their framework to pursue the acquisition of PFGE capabilities. HHS/CDC facilitated the establishment of electronic communications among the participants to stimulate interaction and exchange of information between the participants. The Public Health Laboratory Centre, Hong Kong is coordinating the activities of PulseNet Asia Pacific in close collaboration with the National Institute of Infectious Diseases, Japan. Countries/areas participating in PulseNet Asia Pacific meetings include Australia, Bangladesh, China, Hong Kong, India, Japan, Korea, Malaysia, New Zealand, Philippines, Taiwan, Thailand and Vietnam. The first PulseNet training workshop for PulseNet Asia Pacific participants was held in Hong Kong, 15-17 March 2004. Several countries (Hong Kong, Japan, Korea, Taiwan and New Zealand) have already established PulseNet networks and are beginning to actively perform real-time subtyping of food-borne pathogenic bacteria. Issues related to funding for establishing and maintaining a central PulseNet database for the Asia Pacific network and for coordinating activities of the network are still to be addressed.

HHS/CDC, in partnership with the Pan American Health Organization (PAHO/INPPAZ), APHL and Instituto Nacional de Enfermedades Infecciosas ANLIS "Dr. Carlos G. Malbrán (Institute Malbrán), organized a meeting in Buenos Aires in December 2003 to explore interest in the region in establishing a PulseNet network. The participants expressed overwhelming support for the establishment of PulseNet America Latina. With high quality administrative support from PAHO/INPPAZ and technical support from Instituto Malbrán, the first PulseNet training workshop was held in Buenos Aires in July 2004. Public health microbiologists from six countries (Brazil, Chile, Colombia, Mexico, Uruguay, and Venezuela) were trained in the first workshop. INPPAZ will house the regional PulseNet database in its facilities in Argentina and provide administrative support and coordination for the network.

EC Rapid Alert System for Food and Feed (RASFF)

The European Community's RASFF was established to provide control authorities with an effective tool for exchange of information on measures taken to ensure food safety. The legal basis of the RASFF is Regulation (EC) N° 178/2002. Article 50 of this Regulation establishes the RASFF as a network involving the Member States (EU + EFTA/EEA), the Commission, and the European Food Safety Authority (EFSA). Whenever a member of the network has information relating to the existence of a serious direct or indirect risk to human health, this information is immediately notified to the Commission under the RASFF. The Commission immediately transmits this information to the members of the network. Without prejudice to other Community legislation, the Member States immediately notify the Commission under the rapid alert system of:

To assist the members of the network, information is classified under two different headings, Alert Notification and Informational Notifications.

Alert Notifications-Alert notifications are sent when the food or feed presenting the risk is on the market and when immediate action is required. Alerts are triggered by the Member State that detects the problem and has initiated the relevant measures, such as withdrawal/recall. The notification aims at giving all the members of the network the information to verify whether the concerned product is on their market, so that they also can take the necessary measures. Consumers can be reassured that products subject to an alert notification have been withdrawn or are in the process of being withdrawn from the market. The Member States have their own mechanisms to carry out such actions, including the provision of detailed information through the media if necessary.

Informational Notifications-Informational notifications concern a food or feed for which a risk has been identified, but for which the other members of the network do not have to take immediate action, because the product has not reached their market. These notifications mostly concern food and feed consignments that have been tested and rejected at the external borders of the EU. Consumers can be reassured that products subject to an information notification have not reached the market or that all necessary measures have already been taken. The Commission publishes a weekly overview of alert and information notifications. As it is necessary to strike the balance between openness and the protection of commercial information, the trade names and the identity of individual companies are not published. This is not detrimental to consumer protection, as a RASFF notification implies that measures have been or are in the process of being taken.

Global Environmental Monitoring System (GEMS)

While not a food-borne disease surveillance programme, the Global Environment Monitoring System/Food Contamination Monitoring and Assessment Programme, commonly known as GEMS/Food, is an example of a successful, internationally coordinated surveillance effort. GEMS began as a joint project between FAO, the United Nations Environment Programme (UNEP), and WHO in 1976. WHO is the implementing agency for the contributing institutions (located in over 70 countries around the world). GEMS' purpose is to compile data on food contamination and human exposure from different countries for global synthesis, evaluation, and presentation. In 1996, GEMS began developing a new data structure and protocols for the electronic data submission. The protocols involve encoding and formatting data in a manner compatible with the database maintained at WHO headquarters. Protocols for aggregate and individual data on contaminant levels in specific food commodities include descriptions of the data fields needed to ensure complete, quality electronic data submissions. Data may be submitted to GEMS/Food using the compatible Operating Programmes for Analytical Laboratories (OPAL I and II), copies of which can be requested from the GEMS/Food Manager. GEMS data are accessible at the WHO website. Uniform implementation and wide accessibility of the GEMS system make it a model for expanded, international food surveillance efforts.

INFOSAN

WHO is in the process of establishing an official International food Safety Authorities Network (INFOSAN) for rapid distribution of specific information concerning food safety. INFOSAN has two major components: 1) INFOSAN Emergency for food safety emergency situations when imminent risk of serious injury or death is present, and 2) an information network for the dissemination of important information about global food safety issues. WHO is in the process of collecting contact point from countries and preparing a handbook for use by the INFOSAN emergency contact points.

Conclusion

While there are no all-encompassing international surveillance systems, examples that serve to illustrate the value of such systems have been illustrated. The structure, function, and interactions between each country's government agencies form the start of an eventually global surveillance, regulatory, and protective framework to curtail the transmission of food-borne diseases. Ultimately, WHO, as the lead international public health organization, could be the focal point of such a global surveillance framework. WHO and FAO, through their collective food safety capability, including the WHO Food Safety Department and the FAO Food Standards Programme, could, with the provision of adequate financial and staffing resources, provide the organizational and scientific capability to support a global food-borne disease surveillance system.

Points of Discussion

The Forum may wish to consider the following points regarding international cooperation on food contamination and food-borne disease surveillance.

· This Paper provides examples of certain national and regional food-borne disease surveillance programmes and international activities associated with their programmes. Are there other major programmes and international activities that should be brought forward?

· The Paper presents certain strategies for advancing international cooperation of food-borne disease surveillance, e.g., more consistent laboratory methodologies, laboratory training, database development). Are elements missing from these strategies? Are there priorities? What strategies should be pursued to better enable international cooperation on food-borne disease surveillance?

· Given the significant resource (trained personnel, laboratory, and database management) requirements for food-borne disease surveillance, what is the best course of action to follow to enhance developing country capability in this area?

· WHO plays a leading international role in food-borne disease surveillance. How best can their role be enhanced in this area?

EMERGING RISKS RELATED TO THE ENVIRONMENT AND NEW TECHNOLOGIES

(Prepared by the FAO/WHO Secretariat)

1. Environmental risks related to conventional agriculture

Farming and nature exercise a profound influence over each other. Farming has contributed over the centuries to creating and maintaining a variety of valuable semi-natural habitats. They shaped an important part of landscapes worldwide and are home to many of the world's richest wildlife. Farming also supports a diverse rural community that is not only a fundamental asset of international culture, but also plays an essential role in maintaining the environment in a healthy state.

Farming is an activity whose significance goes beyond simple food production. Throughout the production chain processes occur that can have an impact on the natural environment and consequently, directly or indirectly, on human health and development. For example, heavy use of pesticides and fertilizers, incorrect drainage or irrigation practices, a high level of mechanization or unsuitable land use can produce environmental degradation. However, abandonment of farming activities can also endanger the environmental heritage through loss of semi-natural habitats as well as biodiversity and landscape associated with them. Likewise, the effect of agricultural production systems on human health directly (farmer's occupational health) or indirectly (consumer's health through food) are increasingly being recognized as an integrated element in the broader evaluation of environmental risks related to agriculture.

The links between the richness of the natural environment and farming practices are complex. While many valuable habitats are maintained by extensive farming, and a wide range of wild species rely on this for their survival, agricultural loss of wildlife can be the result of inappropriate agricultural practices and land use.

Discussions on possible future environmental effects of new technologies in food production will necessarily have to take outset in the present situation of agricultural effects on the environment, including derived effects on human health, recognizing that present trends of conventional agriculture are likely to be reflected in the objectives of modern food production.

1.1 Key aspects of environmental pollution and resource depletion^[21]

Agriculture adds to greenhouse gas (GHG) problems. There are three main sources of GHG emissions from agriculture: N2O (nitrous oxide) emissions from soils, mainly due to nitrogen fertilization; CH4 (methane) emissions from intestinal fermentation, CH4 and N2O emissions from manure management. Measures being considered include: encouragement of more efficient fertilizer applications to reduce overall use, composting and improvements in anaerobic digestion systems (e.g., for production of biogas), to deal with biodegradable by-products and waste; renewed emphasis on biomass production, conservation tillage and organic farming. Further development of renewable, agricultural biomass could contribute to reductions in emissions from energy and transport, while benefiting the agricultural sector.

Water pollution by nitrates from agricultural sources, where improved agricultural practices are thought to improve pollution.

Pesticides have been proven to have an effect on the environment and ecosystems by reducing biodiversity, especially by reducing weeds and insects which are often important elements of the food chain e.g. for birds. In addition, human health can be negatively affected through direct exposure and indirect exposure, e.g. via their residues in agricultural produce and drinking water. Systems to reduce the need for pesticide use, especially integrated pest management, organic farming or in some cases genetically modified crops are increasingly investigated at national and international level^[22].

Soil degradation processes such as desertification, erosion, decline in soil organic matter, soil contamination (e.g. by heavy metals), soil sealing, soil compaction, decline in soil biodiversity and salinization can cause soil to lose its capacity to carry out its main functions. Such degradation processes can result from inappropriate farming practices such as unbalanced fertilization, over abstraction of groundwater for irrigation, improper use of pesticides, use of heavy machinery, or overgrazing. Measures to prevent soil degradation include support to organic farming, conservation tillage, the protection and maintenance of terraces, safer pesticide use, integrated crop management, management of low-intensity pasture systems, lowering stock density and the use of certified compost.

Irrigation can also lead to environmental concerns, such as over-extraction of water from subterranean aquifers, irrigation driven erosion, soil salinization, alteration of pre-existing semi-natural habitats and, secondary impacts arising from the intensification of the agricultural production permitted by irrigation.

Bio diversity conservation: In recent decades, the rate of decline and even disappearance of species and related habitats, ecosystems and genes (i.e. biodiversity) has increased throughout the world. Declines in biodiversity are of direct consequence for food security when they affect food related organisms and relatives with relevance for breeding. Furthermore, intensified agriculture including modern breeding systems has resulted in significant reductions of landraces, adapted to local specificities as well as traditional knowledge.

Assessment of agricultural impacts on the environment requires the use of holistic models which are able to integrate multiple sources of information^[23]. Previous scientific discussions have concluded that solutions applied at farm level contributed environmental problems but they are not adequate to the task of realizing long-term environmental goals. This requires system innovations at higher levels of aggregation, involving, for example, looking for opportunities to negotiate recycling systems by linking sectors within agriculture and other areas affecting the environment, e.g. transport systems^[24].

As a consequence of public discussion, new concepts for policies of agriculture and environment interactions have been developed in many countries including an improved public monitoring and responsibility for sustainability.^[25],^[26]

The Millennium Ecosystem Assessment (MA), launched by U.N. Secretary-General Kofi Annan in June 2001, is an international work programme designed to meet the needs of decision makers and the public for scientific information concerning the consequences of ecosystem change for human well-being and options for responding to those changes. The MA focuses on ecosystem services (the benefits people obtain from ecosystems), how changes in ecosystem services have affected human well-being, how ecosystem changes may affect people in future decades, and response options that might be adopted at local, national, or global scales to improve ecosystem management and thereby contribute to human well-being and poverty alleviation.^[27]

Work on agro-environmental indicators provided information on the current state and changes in the conditions of the environment in agriculture. It also resulted in a better understanding of linkages between the causes and impacts of agriculture on the environment, looking at agricultural policy reform, trade liberalization and environmental measures. This all contributes to monitoring and evaluating the effectiveness of policies addressing agri-environmental concerns.^[28] A review of empirical work in OECD countries on effects of agricultural policies and practices on the environment is given by OECD.^[29] Work on environmental health indicators suggests that various agricultural practices have direct or indirect effects on human health via environmental effects. Hazards can take many forms, wholly natural in origin or derived from human activities and interventions.^[30]

1.2 Approaches for environmental protection and values to be protected

In 1992 the Convention on Biological Diversity (CBD, ratified by 188 countries) defined a legally binding instrument for biodiversity protection and sustainable use of biological resources.^[31] According to the CBD, biodiversity means "the variability among living organisms from all sources including, inter alia, terrestrial, marine, and other aquatic ecosystems and the ecological complexes of which they are part" (CBD, 1992^[32]). The goal of the Convention on Biological Diversity is "the conservation of biological diversity, the sustainable use of its components and the fair and equitable sharing of the benefit arising out of the utilization of genetic resources." The treaty recognized the great value of genetic and biological diversity.

Biological diversity is closely linked to human interests. Biodiversity is highly important for several quite different reasons: the value of species in the wild, the many varieties of plants, animals and microorganisms used for farming and other human activities worldwide, as a genetic resource in healthcare, agriculture and food production. It provides a source of significant economic, aesthetic and cultural benefits. The well-being and prosperity of earth's ecological balance as well as human society depend directly on the extent and status of biological diversity.^[33]

Naturalism and nature protection: Some difficulties for environmental protection derive from different interpretations and understanding of the idea of nature. Especially in the consumer's debate on the creation of genetically modified organisms, the idea of the need to protect nature was often not well defined, mainly because of differences in the understanding of the concept of nature, ranging between concepts of wilderness, human environment, flexibility of natural systems^[34] and ideas of naturalism.^[35] Ethicists try to improve this situation by using clear definitions, whichever school they might come from (Nuffield report).^[36]

Levels of protection may vary as goals range from sustaining ecosystem services to fully preserving endangered species or fragile protected areas. Biotic homogenization that decreases regional biotas and functional diversity would reduce resilience by reducing the available range of species-specific responses to such environmental changes as droughts, contaminants, or invasive species.^[37] Therefore, different criteria for protection will be needed for different management goals and socio- ecological contexts. The links between environmental protection and human health through the control of direct and indirect health effects of environmental deterioration needs to be factored into these equations, notably with food safety as one of the direct indicators.

2. Emerging new technologies in food production

Following adoption of hybrid breeding technologies further breeding objectives included methods for the introduction of increased genetic variability using several methods for mutagenesis such as chemical mutagenesis or irradiation as well as various ways of tissue cultures. The further development resulted in the presently most advanced methods of modern biotechnologies, the production of organism by genetic modification using introduction of defined new or recombinant genetic material by vectors and transformation methods. These organisms are typically named Genetically Modified organisms or GM organisms. Improved methodology for the development of GM organisms (GMOs) by homologous recombination may ultimately reduce the potential for unintended effects, including health effects, of the inclusion of new genes randomly in the genome, stemming from present technology. Likewise improved methods for a molecular containment of recombinant genes may reduce problems of unintended gene dispersal.

Conflicting assessments and incomplete substantiation of the benefits, risks and limitations of GM food by various scientific, commercial, consumer and public organizations have resulted in national and international controversy regarding their safe use as food and safe release into the environment. An example is the recent debate on food aid that contained GM material offered to countries in southern Africa in 2002. This international debate has often been focused on human health and environmental safety of these new products.

At present, only a few food crops are permitted for food use and traded on the international food and feed markets. These include herbicide- and insect-resistant maize (Bt maize), herbicide-resistant soybeans, rape (canola) oilseed and insect- and herbicide-resistant cotton (primarily a fibre crop, though refined cottonseed oil is used as food). In addition, several government authorities have approved varieties of papaya, potato, rice, squash, sugar beet and tomato for food use and environmental release. Further development of GM crops is likely to produce a range of GM crops with enhanced nutritional profiles.^[38] Various novel traits are currently being tested in laboratories and field tests in a number of countries, but are unlikely to enter the market for several years. A significant proportion of these traits relates directly to human health, the beta-carotene (Vitamin-A precursor) rich "golden rice" as the most well-known example. Other examples with health implications are removing allergens and anti-nutrients, altering fatty-acid profiles and increasing the anti-oxidant content. All new products related to such potential health benefits will naturally need to be scrutinized through thorough environmental and food safety risk assessments.

An analysis of risks and effects of food production practices using modern methods of biotechnology needs to reflect on all developments in the area, based on knowledge of modern biology and keeping in mind that the definition of modern biotechnology is often not very standardized.

Integrated pest management (IPM) needs to be seen in the light of modern biotechnology because of the use of advanced bio-technological methods: Definitions of IPM cover a range of approaches: from safe use of pesticides, to elimination of virtually all pesticide use. Suitable pest control methods should be used in an integrated manner and pesticides should be used on an "as needed basis" only, and as a last resort component of an IPM strategy. In such a strategy, the effects of pesticides on human health, the environment, sustainability of the agricultural system and the economy should be carefully considered. According to FAO, IPM programmes are designed to generate independence and increased profits for farmers, and savings on foreign imports for governments. IPM enables farmers to make informed decisions to manage their crops.^[39]

Sometimes also organic farming is discussed as a modern technology for food production, where farmers adhering to this idea are aiming for similar objectives like IPM but more clearly pronounce the ideas of integrity, self determination and co evolution.^[40] Although organic farming will inherently affect the use of agricultural chemicals, the safety considerations related to food derived from these practices do not only contribute positively in the broader health equation.

2.1 Environmental risks related to food production using GM technologies

Principles of the environmental risk assessment, ERA: In many national regulations the elements of the ERA for GM food organisms include the biological and molecular characterizations of the genetic insert, the nature and environmental context of the recipient organism, the significance of new traits of the GMO for the environment, and information on the geographical and ecological characteristics of the environment in which the introduction will take place. The risk assessment focuses especially on potential consequences on the stability and diversity of ecosystems, including putative invasiveness, vertical or horizontal gene flow, other ecological impacts, effects on biodiversity and the impact of presence of GM material in other products.^[41]

Internationally the concept of familiarity was developed also in the concept of environmental safety of transgenic plants. The concept facilitates risk/safety assessments, because to be familiar, means having enough information to be able to make a judgment of safety or risk (U.S. NAS, 1989). Familiarity can also be used to indicate appropriate management practices including whether standard agricultural practices are adequate or whether other management practices are needed to manage the risk (OECD, 1993). Work of international organizations on biosafety in summarized chronologically by ICGEP.^[42]

Currently the Cartagena Protocol on Biosafety to the Convention on Biological Diversity is the only international regulatory instrument which deals specifically with the potential adverse effects of genetically modified organisms (known as Living Modified Organisms (LMOs) under the Protocol) on the environment. The Biosafety Protocol covers transboundary movements of any genetically modified foods that meet the definition of LMO. Annex III of the Protocol specifies general principles and methodology for risk assessment of LMOs. The Protocol establishes a harmonized set of international rules and procedures designed to ensure that countries are provided with the relevant information, through the information exchange system called "Biosafety Clearing-House". This Internet-based information system enables countries to make informed decisions before agreeing to the import of LMOs. It also ensures that LMO shipments are accompanied by appropriate identification documentation. While the Protocol is the key basis for international regulation of LMOs, it does not deal specifically with GM foods and its scope does not consider GM foods that don't meet the definition of an LMO. Furthermore, the scope of its consideration of human health issues is limited, given that its primary focus is biodiversity, in line with the scope of the Convention itself.

Potential unintended effects of GMOs on non target organisms, ecosystems and Biodiversity: Potential risks for the environment include unintended effects on non target organisms, ecosystems and biodiversity. Insect resistant GM crops have been developed by expression of a variety of insecticidal toxins from the bacterium Bacillus thuringiensis (Bt). Detrimental effect on beneficial insects or a faster induction of resistant insects (depending on the specific characteristics of the Bt proteins, expression in pollen and areas of cultivation) have been considered in the environmental risk assessment (ERA) of a number of insect protected GM crops. These questions are considered an issue for monitoring strategies and improved pest resistance management, which inherently can affect food safety in the longer term. WHO/ANPA, 2000^[43] increased doses of herbicide can be applied post emergence to herbicide tolerant crops, thus avoiding routine pre-emergence applications and reducing the number of herbicide applications needed. Under certain agro-ecological situations, such as a high weed pressure, the use of herbicide tolerant crops has resulted in a reduction in quantity of the herbicides used, in other cases no herbicide reductions or even the need of increased herbicide uses have been reported.^[44]

Out-crossing: Out-crossing of transgenes has been reported from fields of commercially grown GM plants including oilseed rape and sugar beet, and has been demonstrated in experimental releases for a number of crops including rice and maize. Out-crossing could result in an undesired transfer of genes such as herbicide resistance genes to non-target crops or weeds creating new weed management problems. The consequences of out-crossing can be expected in regions where a GM crop has a sympatric distribution and synchronized flowering period, that is highly compatible with a weedy or wild relative species as demonstrated e.g. for rice.^[45] In view of the possible consequences of gene flow from GMOs the use of molecular techniques to inhibit gene flow has been considered and is under development.

GM animals: The possibility that certain genetically engineered fish and other animals may escape, reproduce in the natural environment and introduce recombinant genes into wild populations is a concern of a report of a recent US Academy of Science study^[46]. Genetically engineered insects, shellfish, fish and other animals that can easily escape, are highly mobile and form feral populations easily, are of concern, especially if they are more successful at reproduction than their natural counterparts. For example, it is possible that transgenic salmon with genes engineered to accelerate growth released into the natural environment could compete more successfully for food and mates than wild salmon, thus endangering wild populations. The use of sterile all-female genetically engineered fish could reduce interbreeding between native populations and farmed populations, a current problem with the use of non-engineered fish in ocean net-pen farming. Sterility eliminates the potential for spread of transgenes in the environment, but does not eliminate all potential for ecological harm. Monosex triploidy is the best existing method for sterilizing fish and shellfish, although robust triploidy verification procedures are essential.^[47]

GM microorganisms: Gene transfer between bacteria belonging to different species, genera or even families has been demonstrated in soil and other systems. Such gene transfer goes on between ordinary microorganisms in all ecosystems, and has also been demonstrated from GM microorganisms to other microorganisms, e.g. for antibiotic resistance genes. The transfer of antibiotic genes to microorganisms present in foods and of clinical importance is an unwanted event relative to food safety, while the very low frequency of such transfer most probably leads to very low levels of concern. Only a limited number of releases of GM microorganisms (e.g. Pseudomonas and Rhizobia) have been permitted mainly to explore the spread and the fate of microorganisms in nature. In some cases released GM bacterial populations have been found to persist in the soil for years. The possible consequences of such on natural communities of soil microorganisms are under investigation Risk assessment in such fields is impeded by a number of factors, such as the limited knowledge of indigenous microorganisms in the environment (only approximately 1% of soil bacteria are currently taxonomically described), the existence of natural transfer mechanisms between microorganisms, and the difficulties in controlling their spread. (FAO/WHO Expert Consultation, GMM, 2001)^[48]

Regional specificity in safety assessments: Contradictory findings as relates benefits or disadvantages for the same GM crop may reflect different agro-ecological conditions in different regions. For example, the use of herbicide resistant crops and the consequent herbicide use could potentially be detrimental in a small sized agricultural area, which has extensive crop rotation and low levels of pest pressure. However, the moderate herbicide use related to these GM plants could be beneficial in other agricultural situations where it might represent a decrease in herbicide use. Presently, no conclusive evidence on environmental advantages or costs can be generalized from the use of GM crops. Consequences may vary significantly between different GM traits, crop types and different local conditions including ecological and agro-ecological characteristics.

In 1999, the UK government asked an independent consortium of researchers to investigate how growing genetically modified (GM) crops might affect the abundance and diversity of farmland wildlife compared with growing conventional varieties of the same crops.^[49] The team found that there were differences in the abundance of wildlife between GM crop fields and conventional crop fields depending from GM crop specificity and site of analysis, but no general trend for or against GM crops. The researchers stress that the differences they found do not arise just because the crops have been genetically modified. They arise because these GM crops give farmers new options for weed control where they use different herbicides and apply them differently.

Monitoring of human health and environmental safety: In the future specific GM organisms may gain approvals for widespread production where the approval may not always include the possibility to enter them also in the human food supply. Examples could be plants or animals used for drug production. In such situations, it will be important to consider whether or not to apply post-market monitoring for unexpected environmental spread of the GM animals or animals and their transgenes in the event that these would pose food safety hazards.

A prerequisite for any kind of monitoring are tools to identity or trace GMOs or products derived from GMOs in the environment or food-chain. Detection techniques (such as PCR) are in place in a number of countries to monitor the presence of GMOs in foodstuffs, to enable the enforcement of GM labelling requirements and for the monitoring of effects on the environment. Attempts to standardize analytical methods for tracing GMOs have been initiated e.g. for use in ISO norms.

The WHO/FAO Expert Consultation on GM Animals, 2003, identified a need for Post Market Surveillance and therefore for product tracing systems in specific cases.

2.3 Potential effect of GMOs on human health mediated through environmental impact

The need to assess indirect effects of the use of GMOs in food production has been emphasized by many countries. Potential environmental health hazards of releases of GMOs in the environment have been discussed in a report by WHO/ANPA where health effects have been suggested as "an integrating index of ecological and social sustainability"^[50]. For example, the production of chemicals or enzymes from contained GM micro-organisms (e.g. chemicals, pharmaceutics or food additives), have contributed significantly to decreases in the amount of energy use, toxic and solid wastes in the environment, thereby significantly enhancing human health and development. A further example of beneficial human environmental outcomes of the use of GM crops is the reduction in the use, environmental contamination and human exposure to pesticides demonstrated in some areas. This has been demonstrated especially through the use of pesticide resistant Bt cotton, which has been shown to decrease pesticide poisoning in farm workers^[51]. Out-crossing of GM plants with conventional crops or wild relatives, as well as the contamination of conventional crops with GM material, can have an indirect effect on food safety and food security by contamination of genetic resources^[52]. The Codex guidelines for the safety assessment of GM foods include the analysis of potential unintended effects, where effects on the environment may result in unintended, indirect effects on human health.^[53]

2.4 Modern methods in plant breeding and effects on diversity

Crop breeding strategies are highly dependent upon preservation of diversity of crops and wild relatives. Many methods of conventional and modern biotechnology can interfere with diversity of organisms which have relevance for further breeding. In crops these methods can often concentrate on the further improvement of few elite lines only. The majority of locally adapted land races e.g. will not be propagated further. Also the system for the protection of intellectual property rights interferes with crop diversity. There is growing scientific and public concern about a rapid decline of diversity, e.g. of land races. On the other hand modern methods of biotechnology can be beneficial for enabling diversity in scenarios where possibilities of conventional breeding are difficult because of sterility and pests, e.g. as discussed for bananas.^[54]

Historically, plant genetic resources were freely provided by developing countries to gene-banks world-wide. Now international policy attaches importance to national ownership of such resources. An important aspect for the future potential of agricultural research is access to genetic resources for researchers on terms that recognize the contributions made by farmers to the conservation and sustainable utilization of these resources.

The International Treaty on Plant Genetic Resources adopted at a conference by the Food and Agriculture Organization in November 2001, provides the legal framework for dealing with the resources on which food security and sustainable agriculture depend. The Treaty gives a directive on the conservation and sustainable use of plant genetic resources for food and agriculture making provision for the fair and equitable sharing of the benefits arising out of their use, in harmony with the United Nations Convention on Biological Diversity (CBD). The Treaty also addresses farmers' rights.

The Treaty establishes a Multilateral System of Facilitated Access and Benefit-sharing (MLS) for key crops, emphasizing the interdependency of countries in terms of plant genetic resources for food and agriculture. The developing countries rich in genetic resources are encouraged to place germplasm in the MLS. The users of the material will sign a Material Transfer Agreement, incorporating the conditions for access and benefit sharing through a fund established under the Treaty. In return, the owners of the genetic resources would get a share of the benefits arising from their use and development in the way of information, technology transfer and capacity building

3. Interaction between environmental risks, food risks and socioeconomic aspects

The U.S. Agency for International Development reported that between 1975 and the year 2000 the world lost 22 percent of its high-potential agricultural land. That's 600,000 square miles, an area equal in size to Alaska. The loss is alarming because, as population pressures mount, agricultural production will have to expand onto medium- and low-potential lands that are not only less productive but also more fragile and susceptible to degradation. Soil is degraded mainly through deforestation, agricultural activities, overgrazing, and overexploitation. Biophysical manifestations include erosion and loss of moisture-holding capacity. But more important, and more complex, are the social and economic aspects. Indeed, some view land degradation as a socioeconomic rather than biophysical problem. For example, population growth increases demand for land on which to grow crops, which often leads to deforestation, shorter fallow periods, and continuous cropping. Short-sighted economic policies often make the problem worse by encouraging farmers to clear new land for cultivation rather than to protect land already under cultivation. Insecure land tenure arrangements discourage farmers from making long-term investments needed for resource conservation.^[55]

The Impacts of trade liberalization: The implementation or reform of agricultural and trade policy creates a complicated set of environmental effects - some negative, some positive, and in some cases linked to food safety issues. The effect of freer agricultural trade on environmental quality depends on a number of factors, such as the mix of post-reform commodities, level of output, changes in production inputs, land use, technical change, and the capacity of the natural resource base to assimilate production impacts. The additional effect of such changes related to food safety will in many cases relate to the existence of food safety systems and experience related to the new or increase food commodity production.

Freer trade improves market access for goods previously governed by quantity restrictions (such as quotas and other non-tariff barriers) and aligns domestic prices closer to world prices. Resource reallocation occurs as prices adjust to market conditions and reflect the availability of resources such as arable land, labour, and other farming inputs. As prices change, farmers respond by altering their crop mix and their input use, buying or selling land, and investing in new machinery. In countries where reform leads to an increase in producer prices, farmers will respond by increasing output, placing more pressure on land use, and/or increasing chemical input uses.^[56]

In addition, trade and health considerations are intimately connected. The use of international standards for traded food, focusing on food safety, but in the future also most likely on environmental issues, will have the potential to improve not only internationally traded food but also local food, and thereby the health of local consumers. This in turn would then favour both health and social and economic development - a true win-win situation. The cooperation between international agencies to focus development in these areas is exemplified by the creation of the STDF (Standards in Trade and Development Facility)^[57] in a joint effort between WHO, FAO, World Trade Organization, World Animal Health Organization and World Bank. This Facility will hopefully provide the means for developing countries to strengthen their systems to comply with international standards to the benefit of both exported and locally consumed food.

4. Ethical aspects in the assessment of environmental risks

International agreements related to nature and food production are summarized in a report from FAO on ethical issues in food and agriculture. They include the value of food, the value of enhanced well-being, the value of human health, the value of natural resources, and the value of nature, whereas the Convention on Biological Diversity recognizes that nature itself is to be valued for what it is. The summary of these objectives shows that all principle arguments usually discussed in a risk benefit evaluation of food biotechnology, especially enhanced productivity for increased food production, equity, health and nature protection, interfere with each other, thus requiring a high level of ethical consideration.^[58],^[59]

There is international agreement that risk assessment, risk management and risk communication are central elements in the management of possibly emerging risks of new technologies for food production where risk assessment needs to be done based on "sound science". But discussions on the use of precaution (by some countries referred to as the precautionary principle) and the need to respect legitimate factors other than the scientific assessment of risk have turned out to be controversial^[60].

Scientific progress on these issues was made in the FAO Expert Consultation on Food Safety: Science and Ethics Rome, 2002: The experts agreed that risk assessment is based on science, but scientific evidence and analysis cannot always provide immediate answers to questions posed. Much scientific evidence is tentative, as the established processes of science include checking and re checking outcomes in order to obtain the required level of confidence. Decisions usually are defended as based on "science," and sometimes on economic costs and benefits as well, which offer seemingly objective, verifiable evidence that the policy choice is "correct." Decisions explicitly based on ethical principles and value preferences can be just as defensible, if the society agrees broadly on the ethical assumptions used to make policy. The emphasis on science and the exclusion of ethical argument as the basis for decisions may polarize the scientific debate.

A cross sectoral group of scientists, NGOs and industry formulated the safety first approach asking for interactive negotiation between research, industry, government and consumers to formulate safety standards. These standards would make safety a criterion in discussions on developments from the beginning and not at the end before product notification and include post market monitoring, training and stewardship.^[61]

The dependence of factors directly relevant for the risk assessment of products of new technologies with socio-economic or ethical factors will be addressed in attempts of an integrated/holistic assessment of possible consequences in an ongoing WHO project.^[62] In the FAO/WHO Expert Consultation on GM Animals, Rome 2003, furthermore, an analysis including ethical criteria was proposed using an ethical matrix^[63] and recently the principles of beneficence and non-maleficience, justice and fairness as well as choice and self determination were proposed for a structured methodological evaluation.^[64]

5. The role of international organizations, capacity building and coordination

Products produced with different methods of modern biotechnology are already produced for local or international markets. Crops, animals or microorganism have been improved according to agricultural objectives where these organisms may display specific characteristics in regard to safety or usefulness in different agro- ecological, socio-economic or cultural areas. A globalized market for food production will most likely trade products of these organisms internationally and the safety measures of the Biosafety Protocol will be of importance in risk prevention. However, possibilities of the protocol are restricted to transboundary movements of LMOs and direct effects on diversity. Furthermore, sufficient technical capacities for coherent analysis may be difficult to achieve in many developing countries and the need for coordinated local as well as international information exchange on complex parameters will require sophisticated technical and scientific capacities. The capacity of the Codex Alimentarius Commission to continue its work on internationally agreed principles and guidelines for a food safety risk analysis framework will be key to a truly global development in this area of integrating the different areas of assessment of new agricultural technologies and ensuring that human health considerations will remain at the core. This will ultimately need measures for capacity building in some countries as well as the intensive engagement of international bodies in coordinated monitoring activities, data collection and data analysis. An engaged cooperation of international organizations, especially UN-bodies will be essential for a successful and equitable development in this direction.

PREVENTION AND RESPONSE TO INTENTIONAL CONTAMINATION

(Prepared by the FAO/WHO Secretariat)

Summary

The malicious contamination of food for political, financial and other purposes is a real and current threat, and deliberate contamination of food at one location could have global public health implications. Member States of WHO have expressed concern that chemical, biological or radionuclear agents might be introduced into food and other media to deliberately to harm civilian populations and have requested the Organization to provide tools and support to increase their capacity to respond. In response, WHO has prepared various guidelines, including guidance to prevent and respond to intentional contamination of food.

While all food safety emergencies, including intentional and unintentional incidents, may be managed by the existing food safety infrastructure, sensible preventive measures coupled with basic preparedness are needed to address threats posed by deliberate contamination. Countries should integrate consideration of acts of food sabotage into existing programmes for assuring the safety of their food supplies. Strengthening of food safety infrastructure will serve to increase countries' capacity to reduce the burden of all food-borne illness caused by chemical and microbial agents and to respond to all contamination incidents. Improved linkages with existing communicable disease control systems will also ensure that surveillance, preparedness and response systems include the necessary metrics to identify food-borne outbreaks in a timely manner and provide relevant information to facilitate an effective and rapid response.

In order to respond effectively and rapidly, countries require alert, preparedness and response systems to public health threats from actual or threatened intentional contamination of the food supply. Coordination with WHO, FAO and other international and regional organizations regarding incidents involving intentional contamination should be considered as an integral part of strengthening of national systems to respond to all food safety emergencies. In particular, countries should actively participate in the WHO Food Safety Authorities Network for Emergencies (INFOSAN Emergency) as the first step establishing essential capabilities and linkages to deal with this problem.

Prevention and Response to Intentional Contamination

1. Introduction

Threats from criminals and other anti-social groups who target the safety of the food supply are already a reality. During the past two decades, WHO Member States have expressed increasing concern about the possibility that chemical and biological agents and radionuclear materials might deliberately be used to harm civilian populations. In recent years, the health ministries of several countries have increased their state of alert for intentional malevolent use of agents that may be spread through air, water or food.

In 2002, the World Health Assembly in recognizing these threats against civilian populations, requested WHO to provide tools and support to countries in strengthening their national systems to respond to the deliberate use of biological, chemical or radionuclear agents^[65]. It also requested WHO to continue to issue international guidance and technical information on recommended public health measures to deal with potential incidents. In response, WHO has prepared various guidelines, including guidance to prevent and respond to intentional contamination of food.^[66]

All countries must have basic systems to prevent or deter deliberate contamination of their food supplies and, if an incident occurs, to respond rapidly to minimize potential health, economic and other adverse effects of such contamination. However, specific countermeasures should be seen as only one aspect of a broader, comprehensive food safety programme, in national and global contexts. The WHO Global Food Safety Strategy^[67] comprises a preventive approach to food safety, with increased surveillance and more rapid response to outbreaks of food-borne illness and chemical contamination incidents. This approach could substantially expand the abilities of countries to protect the safety of their food supplies against natural and accidental threats, while providing a framework for addressing intentional contamination of food.

For the purpose of this paper, intentional food contamination is defined as an act or threat of deliberate contamination of food for human consumption with chemical, biological or radionuclear agents for the purpose of causing injury or death to civilian populations and/or disrupting social, economic or political stability. The chemical agents in question are man-made or natural toxins, and the biological agents referred to are pathogenic microorganisms, including viruses, bacteria and parasites, that may be communicably infectious or non-infectious. Radionuclear agents are defined in this context as radioactive chemicals capable of causing injury when present at unacceptable levels. This paper covers all foods, including water used in the preparation of food, as well as bottled water.

2. Prevention

As with all health and safety problems, prevention is usually the most desirable option. Prevention is considered first line of defence against intentional contamination. The key to prevention is awareness of this potential threat and the implementation of basic security and precautionary measures. Working in cooperation with government, the food industry is in the best position to rapidly address such threats throughout the food supply system from production to consumption. Government food safety authorities may provide necessary guidance and other coordination functions to assist industry, as in the case of product tracing and recall. As production methods and quality programmes are often proprietary, the food industry has both the knowledge and the capacity to reduce the likelihood of deliberate contamination of food, from the raw materials to product distribution. Governments should support industry in strengthening existing food safety management systems, to include consideration of deliberate contamination. Governments also have a role in promoting preventive food safety, through various voluntary and regulatory mechanisms^[68]. It is important to note that a number of the preventive activities described in this paper relate to 'industrialized' food production systems. Although industrialized production probably also present the most likely targets for intentional contamination, it is very likely that more traditional production systems, including systems with short distribution lines, present problems that need separate consideration.

2.1 Strengthening food safety management programmes

Food can be contaminated deliberately by chemical, biological or radionuclear agents at any point in the food chain. Food safety management programmes offer opportunities for the prevention, detection and control of food sabotage. Understanding the relationships between the production system, ingredients, people, utensils, equipment and machinery can help in identifying where critical failures of the system might occur. Methods of sabotage and the extent of a threat might be identified as a part of this analysis and would provide the basis for a risk analysis. Typical food safety management programmes within the food industry, include good agricultural and manufacturing practices and 'hazard analysis and critical control point' (HACCP) systems. Newer systems based on a scientific assessment of the risk are now increasingly being used to develop risk reduction options along the food supply continuum from farm to table.

Governments should work closely with industry to incorporate prevention and response to intentional contamination into food safety management programmes. Not all countries have the infrastructure needed to assist industry, especially small and less developed businesses, to apply such programmes throughout the food production, processing and preparation continuum. Capacity building for such competence is vital for the prevention of both intentional and unintentional contamination of food. The generic actions that may be taken by governments to assist industry in this respect include:

• cooperating with industry to develop protocols for assessing the vulnerability of individual food businesses, including assessments of the facility and personnel, and potential ways in which food might be contaminated maliciously;

• ensuring that food safety is addressed and controls are coordinated at all links of the food chain, especially traceability and recall;

• cooperating with industry to strengthen the security of processes, people and products;

• providing industry with information on known or possible biological, chemical and radionuclear agents as well as specific threats;

• cooperating with industry to develop, implement, review and test crisis management plans; and

• coordinating closely with industry in communicating with the public.

Prevention of intentional contamination does not always require high technology or great expense. Increased awareness of the problem and enhanced vigilance are among the effective measures that can be taken. Awareness can be heightened by auditing food safety management programmes. In the event of an incident, information from early surveillance could be shared with the food industry to facilitate prompt action to address consumer concerns and contain and mitigate the threat.

2.2 Prevention in the food industry

The knowledge and capacity to prevent deliberate sabotage of food lies mainly with the food industry and must be applied throughout the food chain. Potential contamination with chemical and biological agents and radionuclear materials and interruption of food supplies need to be considered in the development and review of food safety management programmes, which may vary from rudimentary to well developed.

Opportunities for deliberate contamination of food can be minimized by increasing the security for both people and premises. All segments of the food industry should consider improving security and response plans for their establishments. For example, sources of raw materials and storage facilities and transport systems could be safeguarded; access to all critical areas in production, processing, transport and storage could be controlled and documented to minimize opportunities for contamination.

Regarding personnel, employers could consider screening their staff to ensure that their qualifications and background are compatible with their work and responsibilities. Sanitation, maintenance and inspection workers, who have access to critical areas, could also be screened from a security perspective. Appropriate mechanisms could be established to allow staff to report suspicious behaviour and activities.

While it is impossible to describe all the possible scenarios for food sabotage, WHO has developed basic guidance for the food industry for strengthening food safety management programmes to prevent intentional contamination of food with harmful agents^[69]. This guidance offers a range of options that should be considered by industry, taking into account available resources and the perceived threat. Plausible risks need to be considered at every point in the food chain to ensure the safety of the food produced. A number of useful documents prepared by certain countries^[70],^[71],^[72] and industries^[73] offer examples and guidance for analysing risks in the production and processing of specific foods. Not all of these documents will be applicable in their entirety to smaller, developing businesses, but the general principles of assessing vulnerability apply across all businesses and sectors^[74],^[75]

3. Response

While preventive measures are essential, the opportunities for intentional contamination of food are just too numerous to ever be able to completely prevent such incidents. However, effective and rapid monitoring and surveillance programmes coupled with preparedness planning can do much to respond to such threats. Many governments have, or are developing, food safety infrastructures to ensure that food produced for both domestic consumption and export meets acceptable safety standards. Strengthening national food safety programmes requires that national policies and resources to support the infrastructure are in place and that food legislation, food contamination monitoring laboratories, food inspection, food-borne disease surveillance, education and training are adequate and up to date. Above all, the possibility of intentional contamination needs to be an integral part of safety considerations.

While most of the knowledge and capacity to prevent food safety emergencies lies within the food industry, governments have a lead responsibility for detecting and responding to actual or threatened food contamination incidents as well as other food safety emergencies. In the event of an intentional food safety emergency, the potential consequences to public health, the economy and social or political stability must be managed by an effective, rapid emergency response system, at all levels. The effectiveness of a response depends to a great extent on preparedness plans that are developed and implemented long before any event occurs. Public health preparedness planning for emergency situations has been considered in some detail in various WHO publications and is therefore not discussed in detail in this document.^[76]

3.1 Assessing vulnerability

The nature of a preparedness and response system is based on an assessment of specific threats of deliberate food contamination and their priorities in relation to other public health problems. The priorities are determined as part of an assessment of vulnerability performed as part of the development of preparedness plans for intentional contamination. Threats could be ranked from high to low, on the basis of their impact on health and their potential social, economic and political consequences.

Vulnerability is assessed on the basis of the prevailing scientific, economic, political and social circumstances of a country, to measure the extent of a threat and to set priorities for resources. Priorities must be set to ensure that the action taken to deal with the threat is commensurate with the severity of the inherent consequences of the threat. The purpose of an assessment of vulnerability is to identify the properties and potential consequences of deliberate contamination of food by harmful agents, to identify relative priorities and to commit national resources in a proportion consistent with these priorities. Technical experts in food and food safety should participate in any assessment of vulnerability specific for intentional contamination. Information on the toxicology of chemicals and the characteristics of microbial agents is a necessary component of such an assessment, together with an assessment of potential exposure, which will determine the potential impact of the agent.

3.2 Preparedness as the foundation for response

Response to emergencies caused by intentional contamination of food has common features to emergencies caused by unintentional contamination. Often the two cases cannot be distinguished, especially during the early phases of an outbreak. For these reasons, preparedness plans should include response to both intentional and unintentional incidents. Where preparedness plans already exist food safety emergencies, intentional contamination of food needs to be integrated into existing plans, making maximum use of existing emergency response infrastructure and resources. The resources and protocols for a medical response, including rapid transport, supplies, personnel and patient evacuation, are an integral part of communicable disease preparedness, and these have been described elsewhere.^[77] A well-designed public health emergency response system should also include the capacity to respond to food contamination incidents. In planning for food safety emergencies, the following points are emphasized:

• Planning should consider the ability of the surveillance and monitoring systems to rapidly detect food safety emergencies, including those caused deliberately;

• Investigation of a potential outbreak identified by surveillance should include identification of the food and the responsible agent in the food; and,

• Response to an incident, where the source or mode of transmission is unknown, should be made concurrently with all the necessary food safety components until the role of food can be ruled out.

For incidents involving intentional contamination of food, effective interaction between emergency response and law enforcement components is very important. Preparedness planning may include specific requirements of the criminal justice system, such as a signed chain of custody for any specimens and other evidence.

Preparedness plans should be tested in exercises involving agencies responsible for emergency responses to intentional food contamination. Any new components should be tested for effective response to intentional incidents. Evaluation of the results of real incidents and emergency response exercises should be used to identify the need for further resources, refine the roles of various agencies and their interaction and improve emergency plans.

The performance of surveillance systems for detecting food-borne disease clusters and epidemiological investigations to identify the food and hazardous agent give an indication of the capacity of the system to respond to intentional incidents. Timely response to food emergencies requires effective linkage of preparedness planning and emergency response systems in all relevant agencies. Linkages with food safety authorities are needed to provide specialized support related to an investigation that may involve food. Availability of qualified food safety inspectors and laboratories are important requirements for preparedness. For example, the timely sampling, transport and analysis of suspected foods should be addressed as part of preparedness planning. Countries need to inventory their laboratory capacities for possible threat agents. Rapid testing for unusual agents, such as dioxin and ricin, can be facilitated by international programmes, such as the Global Environment Monitoring System/Food Contamination Monitoring and Assessment Programme (GEMS/Food), which maintains a network of food safety laboratories in over 80 countries around the world.^[78]

3.3 Strengthening food safety within existing public health emergency response systems

Public health preparedness and response systems focus mainly on communicable diseases, and most emergency response systems do not yet include consideration of the use of food as a vehicle for threat agents. Few countries are able to respond rapidly and effectively to intentional food contamination in their current state of development. Food safety emergency response may be initiated by either a plausible threat or an actual act of deliberate contamination of food.

An effective public health response to a deliberate food contamination incident will depend on the timeliness and quality of communication among numerous agencies and sectors, including health services, public health authorities at local and national level, clinicians, infectious disease specialists, laboratories, poison information centres, forensic pathologists, other agencies and organizations and the food industry. An effective emergency response must also be tailored to the circumstance and should include links with law enforcement and intelligence agencies, tracing and food recall systems, risk assessment specialists and the food industry as well as the more traditional sectors of health care providers, laboratories and emergency services.

Linkages between existing national alert and response systems and food safety systems allow effective detection of and response to such incidents. Improved links with food safety agencies will allow access to relevant information about food and about methods and analytical techniques for testing food and harmful agents. Experts in food safety could assess the risks associated with chemicals and microbiological hazards to ensure that the response is proportional to the risk. Identification and recall of affected foods are important features of a food safety emergency response. Tracing information is necessary for estimating the scale of potential exposure and for removing the affected food from sale. It may also assist in a criminal investigation of a food contamination incident. Recalls are usually implemented by the food industry in cooperation with food safety authorities. Quarantine and customs agencies have information about food imports necessary for tracing and recall and can undertake rapid seizure of food at the point of entry. Coverage 'from farm to fork' needs to be incorporated into response planning for food safety emergencies, including the intentional contamination of the food supply.

Finally, the recovery of the food supply system needs to be considered as part of a response system. Verification of the effectiveness of the response in removing or otherwise decontaminating the food involved is necessary before relaxing restrictive measures and reassuring consumers of the safety of the food supply. While situations will vary, continued sampling and analysis will likely be a common feature of most recovery scenarios.

3.4 Communication

Swift and effective communication among all components of an emergency response system is essential and should be included in preparedness planning. Communication with international components, such as Global Outbreak Alert and Response Network (GOARN)^[79] and the International Food Safety Authorities Network for Emergencies (INFOSAN Emergency)^[80], should be considered essential in the light of the potential international spread of disease and trade in food. The FAO/WHO Codex Alimentarius Commission has recently provided guidance on the sharing of exchange of information during food safety emergency situations.^[81] Secure web-based resources can facilitate communication during an emergency response.

Because perpetrators may sometimes seek to create panic and fear in the population, good communication with the mass media and the public is essential during a food safety emergency and should be included in preparedness planning. Timely press releases and other information should be released to the public to prevent unwarranted speculation and to forestall rumours. Food safety experts with good communication skills are valuable for this purpose. A balanced approach should provide information without unnecessarily increasing anxiety. Cultural aspects should be considered in communications about threats and incident response. An FAO/WHO publication on risk communication for food safety matters provides some guidance on this issue.^[82] Suggestions for communication during outbreak situations are also available in other WHO publications.^[83]

An effective communication channel should be opened with the relevant food industry to share information with government authorities about intentional contamination incidents. In communicating with the public, some industry bodies have developed protocols for responding to such threats and have formulated model questions and answers for dealing with such situations.

4. Conclusions

The key to prevention of intentional contamination of food is to promote awareness of this potential threat. Working in cooperation with government, the food industry is in the best position to rapidly address such threats through implementation of basic security and precautionary measures. Government food safety authorities may provide necessary guidance and other coordination functions to assist industry, as in the case of product tracing and recall.

The emergency response to intentional contamination incidents needs to follow detailed and thoroughly tested preparedness plans. The responsibilities of lead agencies, whether they be health agencies responding to a medical emergency, law enforcement agencies responding to criminal acts or food safety authorities responding to a contaminated food, need to be clearly identified as part of the plan. Emergency response plans to food contamination threats require a high degree of cooperation among public health and law enforcement agencies of governments, as well as with the food industry. Food safety agencies can coordinate tracing and food recalls, and generally have well-established links with the food industry to effect rapid removal of unsafe food from circulation. Finally, the recovery phase following an incident should be emphasized to restore availability of safe food to the market as soon as possible. Again, a close working relationship with the food industry is necessary to reassure consumers that the incident has been resolved.

A few developed countries have taken significant steps in safeguarding their food supplies against intentional contamination. Many developing countries are only beginning to take action. However, even with the best precautions in place, no country is immune to public health emergencies caused by unsafe food considering the potential for natural, accidental and intentional contamination. With the globalization of the world's food supply, coordination of efforts internationally is increasingly seen as vital to the rapid detection of incidents, identification of causative agents and foods and the prompt and effective response to contain and mitigate any adverse health and economic effects. The management of threats to food safety in the Twenty-first Century, including intentional contamination, requires countries to maintain sensitive and rapid alert systems, detailed and well-tested preparedness plans and rapid and effective emergency response systems with links to relevant international networks.

Communication and sharing information through internationally coordinated networks will provide timely risk assessment and management. Coordination with WHO, FAO and other international and regional organizations regarding incidents involving intentional contamination should be considered as an integral part of strengthening of national systems to respond to all food safety emergencies. In particular, countries should actively participate in the INFOSAN Emergency as the first step establishing international communications and building essential capabilities to deal with this problem. WHO is now in the process of preparing a handbook for INFOSAN Emergency contact points that will provide practical guidance in preparedness and response to intentional contamination incidents.

Finally, it is important to recognize that while countries must address all plausible threats to their food production systems posed by intentional contamination, resources for more traditional food-borne disease outbreaks, including the so-called "silent epidemic" consisting of large numbers of sporadic cases, need to be maintained. These traditional outbreaks are presently causing major problems for health and development, especially in developing countries. This again emphasizes the need for ensuring that prevention and response systems in food safety be considered in a fully integrated manner, irrespective of the source of the outbreak.