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Capacity building for surveillance and control of zoonotic disease under emergency conditions


Paolo Pasquali[9],[10], Umberto Agrimi[11], Renata Borroni[12], Luca Busani[13],[14], Caterina Graziani[15], Marco Leonardi[16], Giovanni Poglayen[17], Agostino Macrì[18],[19] Adriano Mantovani[20].

Veterinary public health is a fundamental part of the public health system in general but it assumes a pivotal role in disaster emergencies, especially in, but not limited to, the prevention of the spread of communicable or zoonotic diseases. During recent years, increasing demands have arisen for veterinary action in calamities, whether natural in origin or man-made.

In emergency conditions following a disaster, the acting system to monitor and control communicable diseases suddenly stops and the best conditions to spread infectious diseases arise. With differences due to the type of disaster that has occurred, the main features that must be considered are the following:

In this scenario, characterized by the occurrence of the best conditions to spread communicable diseases along with the ceasing of the pre-existing control measures, it is likely that infectious diseases, especially those of zoonotic origin, will pose serious risks to public health. Here we will discuss the approach in emergency conditions from a veterinary public health point of view, focusing on, but not limiting to, the control on the zoonoses. The implementation of a strategic plan in emergency conditions following a disaster is a project that needs a detailed and long-term design. A disaster requires an immediate, intensive, specialized response to be provided in very limited time and space, often in extreme conditions. It is, therefore, impossible to deal with a disaster if there is not a prepared plan of action. It is envisaged that every country organizes its own veterinary emergency organization inside its veterinary services. The aim of this organization is evident and relies on the preparedness in normal conditions and on the implementation of strategic plans in emergency conditions.

The principal aspects that a veterinary emergency organization would have to take into account are the definition of a strategic policy to pursue in normal conditions and the identification of veterinary responsibilities during the phases following an emergency. The main relief actions that a veterinary task force is expected to provide in a stricken area are:

An emergency is a sudden occurrence demanding immediate action following a disaster. The strategic impact of an emergency is deeply connected to the context of the social, political and epidemiological circumstances in which it occurs. A disaster can be defined as:

1. a dramatic change in human ecology with which the stricken community is unable to cope using only its own resources; or

2. any occurrence that causes damage, ecological disruption, suffering or loss of health on a scale sufficient to warrant an extraordinary response from outside the affected community or area.

TABLE 1
NATURAL AND ARTIFICIAL DISASTERS
NATURAL

ARTIFICIAL (man-made)

Earthquakes

Explosions and fires

Flooding

Chemical escape and contamination

Avalanches and landslides

Escape of radioactive materials

Volcanic eruptions

War

Storms

Collapse of dams

Drought and famine

Large-scale poisoning

Epidemic diseases


Insect swarms


In the organization of any relief action three different phases can be recognized.

RECOGNITION PHASE

This phase consists of the collection and analysis of as much information as possible on the status of the structures and services. Studies should be directed towards the identification of reliable indicators for a rapid epidemiological evaluation of a disaster situation. They should be relatively simple in order to allow immediate decision-making. In particular, it is of paramount importance to acquire information on:

A list of the priorities to be dealt with can then be established.

EMERGENCY PHASE

This should be concerned with the identification of suitable patterns of action according to the kind of area, by defining broad responsibilities. Organization and implementation should take into consideration needs and resources available.

Immediate action (first few days after the disaster)

Secondary action (first few weeks after the disaster)

RESTORATION PHASE

The last phase should plan the re-establishment of normal activities. It looks to long-term objectives for the few months after a disaster and that tend to be lasting. Restoration can be accomplished and, after that, a surveillance system provides information about the impact of assistance and the emergency plan.

Of particular interest are:

Every effort has to be programmed to focus if there are major modifications of the ecological environment that will permanently alter the predisaster situation. If such conditions do not occur, the strategic plan has to re-establish the pre-existing situation. If the disaster has had an impact that has substantially modified the ecological conditions of the area, it is important to evaluate how the new conditions could influence veterinary public issues, and how to plan to contribute to the prevention of communicable diseases and to support animal health and production.

As already discussed, every plan to provide assistance in emergency conditions relies on a well-planned preparedness that necessarily has to be made in normal conditions. In fact, when a disaster occurs an extensive mobilization of people generally follows, but often such people are unprepared to face emergency situations and they may create a further problem. To overcome this difficulty it is necessary not only to plan for a trained task force to use in emergency scenarios but it is highly advisable to promote a continuing education system in topics related to emergency conditions for people who could be involved in disasters. In particular, people concerned with animals, veterinarians, and public health specialists should have a general understanding of the problems related to disasters. It is important that these people are adequately trained, especially in the areas of veterinary public health and animal health problems related to disaster situations, and in responsibility and tasks in relief operations and legislation. In an attempt to illustrate the importance of the surveillance and control of zoonotic diseases in emergency situations, we have tried to characterize some pivotal features that are discussed in the following sections.

ANIMAL CARCASSES DISPOSAL IN EMERGENCY SITUATIONS

Most emergencies pose problems connected with carcasses and/or animal products that need to be destroyed. The disposal of these items is affected by many factors. The most relevant of these are:

These and other factors, sometimes connected with local and or international trade, influence veterinary public health actions. Even though the subject of carcass disposal is extremely wide and affected by many variants because of different local situations, necessities and legislation, we will limit our presentation to two main items: veterinary epidemic and non-epidemic emergencies.

Epidemic emergencies

Epidemic veterinary emergencies are outbreaks of infectious animal diseases (mainly diseases included in the OIE "list A"). They may represent not only a serious danger for animal health and welfare and an economic threat to animal livestock industries, but also primarily a risk for human public health, as in case of zoonotic infections. Often, in epidemic emergencies, a significant number of carcasses are to be disposed of not only due to mortality from disease, but also because culling is one of the main tools adopted to eradicate an animal epidemic outbreak. Epidemic emergencies may strike wildlife, zoo animals, pets and livestock, and the increasing concentration of livestock production could significantly magnify the number of farm animals involved in such an outbreak. Recent outbreaks of foot-and-mouth disease and of avian influenza clearly show the importance of efficient management of carcasses. Moreover the risk of transmissible spongiform encepahlopathies, together with the development of standards to increase environmental sustainability and a growing social sensibility, preclude the application of procedures for animal carcasses and wastes disposal that heretofore were considered to be acceptable. All legal authorities involved must be identified in advance, and connections to industries established, to allow immediate actions when necessary. Veterinary services must assume primary leadership and coordination of all activities linked to the control of animal outbreaks, because they have the professional competence and training. Animal diseases control depends on the speed with which control measures can be taken. Pre-emptive culling is one of these measures and requires an increase in culling and rendering capacity. Consequently in emergency management plans it is imperative to determine in advance what technical pathways and capacities are available at each step, for animal slaughter, storage and disposal of carcasses. Generally, in epidemic outbreaks culling and rendering capacities represent two bottlenecks.

Priority in the use of rendering plants may be fixed as follows:

1. carcasses from infected farms and carcasses from farms where animals show clinical signs of disease;

2. carcasses from farms where pre-emptive culling has been performed and where there had been no suppressive vaccination;

3. carcasses from farms where pre-emptive culling was performed and where there had been suppressive vaccination; and

4. carcasses of animals killed as a result of welfare problems.

If cold storage plants are present in the restricted area, deep-frozen carcass may be stored and delivered to rendering plants when rendering capacity becomes available. The end-products of the rendering process could be stored and, in agreement with local regulation, used by pet-food industries, for biogas production or composting, or alternatively incinerated.

Non-epidemic emergencies

In non-epidemic emergencies a certain number of animals die and their carcasses have to be disposed of. The number and kind of dead animals may vary depending on the nature of the events and on the geographical and anthropic characteristics of the affected territory. Flood that devastated Eastern Europe during 2002 caused the death not only of livestock and pets but also of many wild and zoo animals. Animal carcasses may be dispersed over a large territory such as in the case of flood or earthquakes, or may be concentrated in a small area, for instance because of road accidents or chemical intoxications. In most disaster situations there is also food of animal origin stored in damaged commercial or domestic refrigerators that needs to be disposed of. The safe disposal of animal carcasses and wastes is a task of the first emergency phase. In natural disasters the quick removal and disposal of dead animals is needed for a variety of reasons.

1. To avoid smell due to decomposition processes. The general belief that carcasses and their smell carry epidemics can cause anxiety among uninformed people.

2. Carcasses and animal wastes represent a source of food for noxious animals such as rodents, necrophagous birds and stray dogs. These animals may spread the remains of carcasses over a large area, increasing the risk of diffusion of diseases, including zoonoses.

3. Decomposition processes of animal carcasses can cause environmental contamination, particularly of the superficial water layer.

4. To avoid the possibility that animal carcasses are utilized as food by local populations without any surveillance, or that they enter the illegal trade with a risk for public health.

5. In some kinds of accidents, for example chemical pollution, it may be useful to identify the causes of death. Carcasses of animal that have died as result of poisoning or use of drugs for euthanasia should not be used as feed for other species; therefore rendering should be avoided or should be followed by incineration.

Management plans may be also designed in advance for non-epidemic emergencies. Plan contents are described in detail in the following section.

Handling of carcasses

Handling of carcasses of animals that have died or been killed during emergencies may involve risks for people participating in their disposal. Therefore, recommendations for the proper handling of carcasses have to be supplied. People who, in the course of epidemic or non-epidemic emergencies, must handle animal carcasses should be provided in advance with protective clothing (disposable water-resistant overalls, disposable gloves or latex gloves inside leather-palmed work gloves, rubber boots, disposable masks) and should be required to use it properly. They should spray carcasses with disinfectant solutions, using a low pressure garden sprayer, being sure to allow the bleach solution to mix thoroughly with blood or secretions from the carcass, before handling. Recently deceased animals may carry ticks or fleas. Sleeves and cuffs are to be closed, and people should use a repellent for insects. Whenever possible, grappling hooks or other tools should be used for the safe handling of carcasses. People should avoid direct contact with their skin, eyes, mouth and nose and, if they inadvertently come into direct contact with carcasses, they should be allowed to clean up as soon as possible. A complete change of clothing, including footwear, is recommended at the end of activities.

Final considerations

Even if culling is the most common and successful approach to control and eradication of epidemic outbreaks in developed countries, it requires considerable technologies for animal carcasses disposal. Moreover, the growing tendency to refuse to waste valuable animal products and the negative environmental impact of technologies utilized for animal carcasses disposal must be considered. Before deciding measures to avoid the spread of epidemics and methods of carcasses disposal, especially in developing countries where food supplies and disposal plants are both very limited, a well-balanced risk evaluation must be done. Depending on the epidemiological situation and in accordance with local regulations, the use as food of livestock that has died in non-epidemic emergencies might be encouraged. Furthermore, in poverty conditions where carcasses of livestock represent a valuable source of food, veterinarians should provide people with any feasible instructions to assure their safe use (e.g. boiling, prolonged cooking).

Management plans for carcasses disposal are essential tools both in epidemic and in non-epidemic veterinary emergencies. Plans must be established well in advance taking into consideration all possible risks, the epidemiological situation, the geographic and geologic characteristic of the area, the social situation and all the available human and technological resources. Efficient management plans need interprofessional cooperation and widespread divulgation among concerned people.

See Tables 2. and 3.

TABLE 2
MAIN ZOONOTIC DISEASES THAT MAY BE TRANSMITTED BY AFFECTED ANIMALS OR CARCASS HANDLING

Disease

Agents

Species

Infected materials

Route of infection

Brucellosis

Brucella spp.

Livestock, wild rodents, carnivores

Foetus, placenta, carcasses, blood, organic fluids

Skin, aerosol

Anthrax

Bacillus anthracis

Warm-blooded vertebrates

Spores in carcasses, blood, organic fluids

Aerosol, skin injuries

Chlamydiosis

Chlamydia psittaci

Birds


Aerosol

Q fever

Coxiella burnetii

Ruminants, birds, wild rodents

Placenta, milk, organic fluids, ticks

Aerosol, ticks

Tick-borne viral encephalitis

Flavivirus

Mammals

Ticks (Ixodes ricinus)

Bites of ticks

Leptospirosis

Leptospira spp.

Livestock, rodents, carnivores

Viscera, blood, urine, organic fluids, water contaminated by urine

Skin excoriations, oral, respiratory and conjunctival mucosa

Rift Valley fever

Phlebovirus

Livestock

Blood and other organic fluids

Bites of mosquitoes, blood, other organic fluids, aerosol

Lyme disease

Borrelia burgdorferi

Rodents, wild hoofed animals

Blood

Bites of ticks

Erysipelas

Erysipelothrix rhusiopathiae

Swine, birds, carnivores

Blood, organic fluids, animals tissues

Skin lesions

Mycobacteriosis

Mycobacterium bovis, M. tuberculosis, M. avium, ex.

Mammals, birds

Many infected tissues

Oral, aerosol, skin lesions

Pseudotuberculosis

Yersinia pseudotuberculosis

Birds, hares

Infected tissues mainly liver and lug

Skin injuries, oral

Rabies

Rhabdovirus

Mammals, bats

Blood, organic fluids, central nervous system

Bites, skin injuries, aerosol

Salmonellosis

Salmonella spp.

Mammals, birds

Blood, infected tissues, faeces

Oral

Tularaemia

Francisella tularensis

Rodents, lagomorphs

Blood, organic fluids, infected tissues

Skin, aerosol


TABLE 3
SELECTED METHODS FOR ANIMAL CARCASS DISPOSAL

Technology

Favourable factors

Constraints

End Products

Rendering:
Closed system for mechanical and thermal treatment of animal tissues

Network of facilities
Closed treatment
Effective inactivation of many pathogens
Established markets for rendered products
Possible disinfections
Possible veterinary control of activities
Possible environmental control of outlets (air, water)

Limited capacity
Fixed location
No inactivation of transmissible spongiform encephalopathy agents
High cost
Possible transport difficulties

Animal fats:
pet food
animal feed
oleo chemistry
biogas
fuel
Animal protein concentrates:
pet food
animal feed
fertilizer
biogas
fuel
landfill

Incineration (fixed):
Established facilities in which whole carcass or carcass portions can be completely burned

Effective pathogen inactivation

Fixed location
Leak-proof transportation of input material required
Low capacity
High cost
High energy consumption
Gas emission

Ash

Incineration (mobile):
Mobile system that can be taken in site
Whole carcass can be completely burned

Effective pathogens inactivation
No transportation required

Limited capacity
High cost
Limited availability of equipment
No environmental control

Ash

Pyre burning:
Open air system of burning carcasses on farm or in other collective sites

Feasible on site
Transportation of input material not required

Possible incomplete combustion and no verification of effective inactivation of all pathogens
Environmental contamination
Logistics for energy supply required
Long period for total combustion required
Lack of public acceptance

Ash

Composting:
Controlled aerobic microbiological decomposition of organic materials
May be operated in open or in closed systems

On-site process
Low cost

Mechanical grinding pretreatment required
Addition of organic material for microbial maintenance required
Long period required
Effectiveness of pathogen inactivation difficult to verify
Uncontrolled emissions to the environment
Compost made from animals not well accepted

Compost

Fermentation:
Closed system of anaerobic microbiological decomposition

Closed system
Energy recovery
Nutrient recovery (fertilizer)

Not suitable for pathogen inactivation
Preventive rendering treatment required

Biogas
Liquid fertilizer

Burial (on farm):
System to deposit whole carcasses below ground level covered by soil

No transportation required
Established procedure

Environmental assessment required (potential contamination of water layer)
Does not inactivate all pathogens
Environmental impact increases with number and size of carcasses
Sites of burial lost for future use
Public lack of acceptance

None

Landfill:
Deposition of carcasses in predetermined and licensed sites

Sites predetermined
Established procedure

Transportation required
Preventive environmental assessment required (potential contamination of water layer)
Does not inactivate all pathogens
Potential problem of disease transmission by birds or necrophagous animals
Sites lost for future use
Environmental impact increases with number of animals involved
Sites are lost for future use
Public lack of acceptance

None

RISK MANAGEMENT AND COMMUNICATION IN ZOONOTIC EMERGENCY

The emergency situation, whatever is the cause, is often characterized by uncertainty about the real situation and the real impact of the event, rapid change in the scenario and in the level of risk, pressure from the media, from public opinion and from stakeholders and, as a rule, scarce information. The involvement of zoonotic agents in public health emergences has occurred in the past, is now happening around the world, and will occur in the future, taking into account the global scenario of zoonoses and the human health related risk. Recent examples of emergencies due to zoonotic agents are avian influenza, SARS, West Nile fever, bacterial food-borne diseases such Shiga-like toxin-producing Escherichia coli 0157 (STEC) and related serotypes, Salmonella spp and others. They can pose a global threat to the public health, owing to their capability to spread across boundaries. Moreover, new threats come from the possible employment of zoonotic agents as biological weapons, as happened in 2001 in the USA, when a number of people were exposed to a terrorist attack by anthrax and five died from the acquired infection. To mitigate these threats, the veterinary and public health institutions must be able to detect threats and determine effective protective actions making best use of internal resources, as well as external emergency services. Moreover, emergency responses as collective actions taken to face an event potentially harmful for people and animals, should aim also to minimize the social and economical consequences. Emergency response planning is the development and implementation of policies, procedures, and organized teams designed to stabilize the effects of an incident. The strategic options available to face these challenges are related tasks outlined below.

Preparedness

The first stage in managing an emergency is to be ready for it. An example of preparedness is the WHO document on global preparedness for pandemic influenza (http://www.who.int/csr/resources/publications/influenza/WHO_CDS_CSR_EDC_99_1/en/), which provides guidelines to countries to improve the capacity for intervention in the case of a new influenza pandemic. In this task some possible scenarios (considering different severities of the disease, different means of spread, different veterinary and public health impact) should be defined for the zoonotic agents at highest risk of introduction and spread. For the different scenarios described, contingency plans should be prepared, defining the resources that should be ensured during the emergency and the participants that should be involved in the intervention. The direct positive effects of defining the intervention strategies in advance are the timely definition of resources and participants that should be involved in the intervention, the identification of any need to address lack of resources before the emergency, and a general positive effect due to the demonstration of efficiency in planning public health intervention. On the other hand, the efforts spent in planning, in advance, intervention strategies to face possible emergency situations is often difficult to justify, particularly in the face of limited resources and more urgent problems and priorities.

Organization and Intervention

Organization is a direct consequence of contingency planning, in which the structure of the intervention is more precisely defined and the different stakeholders involved are identified. In this phase it is important that clear definitions of the activities and duties are established, in order to ensure that, in an emergency condition, the activities necessary to manage the crisis are carried out. To test the intervention capability, some simulation exercises should be undertaken, following the recommendations of the OIE and other international bodies (http://www.oie.int/eng/info/en_prepaurgence.htm). In the case that the emergency occurs, the contingency plan is put into force. A crucial activity to perform at the early stage of the intervention is collection of information about the situation. This activity is very important both for driving the intervention measures and for releasing appropriate communication to the stakeholders and to public opinion. As a general rule, the intervention options to manage the emergency are:

During the intervention, the crisis evolution should be monitored, to evaluate the effectiveness of the measures put in place. When the emergency is over, a critical evaluation of the intervention measures put into force and of the performance of the teams and resources involved is required. This evaluation should identify the strengths and weaknesses of the intervention measures, appropriateness of resources and staff involved, and effectiveness of communication released. The main purpose is to learn from the experience and refine the resources allocation and the intervention measures.

Communication

Crisis and emergency risk communication is the attempt by science or public health professionals to provide information that allows individuals, stakeholders or an entire community, to make the best possible decisions about their well-being, under time constraints, and to communicate those decisions, while accepting the imperfect nature of their choices. Communication during an emergency is a crucial task for the institution involved to perform, in order to respond to public opinion, stakeholders and other interested subjects about the event that has occurred. The communication must be planned in order to ensure effectiveness and transparency in each phase of the crisis, taking into account the difficulties and constraints caused by the evolving situation. A good example of how to organize communication during emergency comes from the experience of the CDC (http://www.au.af.mil/au/awc/awcgate/cdc/cerc_book.pdf) in managing communication during emergency.

SURVEILLANCE AND CONTROL OF ZOONOSES IN NON-EPIDEMIC EMERGENCIES

Veterinary public health action is required for control of zoonoses, and food provision and safety, in major and minor emergencies. This action has three main peculiarities:

1. the potentiality of veterinary contribution (often overlooked) in animal diseases and zoonoses control, and in food provision and safety;

2. the duty to preserve not only the life and health, but also the economy (the long-term survival); and

3. the necessity to act interprofessionally.

Veterinary action has been involved in food provision and safety, zoonoses prevention, care of animals, control of animal disease, and surveillance in refugee camps. A veterinary component is often part of rescue teams sent from outside the areas involved. This action implies two main items:

1. The preparation of veterinary services to face an emergency; the action for epidemic and non-epidemic emergencies have many overlapping points. We shall limit our discussion to non-epidemic emergencies.

2. The action for zoonoses. We will discuss five examples:

ACTIVITIES OF VETERINARY SERVICES

The main responsibility should fall mostly on local veterinary services, as external aid has scarce knowledge of the territory and of the human and animal populations. Whenever possible, local veterinary services should be especially trained and have the following information concerning their area, which, if available, is important for any rescue action:

1. large and minor emergencies that have occurred or may occur - earthquakes, volcano eruptions, floods, industrial and road accidents, etc.;

2. number, location, social composition, food necessities, habits and taboos of the human population;

3. number, location, production, housing, pasturage of farm animals;

4. feed, water and other provisions available or needed for animals;

5. special needs of farm animals - e.g. housing, milking;

6. number, species and location of companion animals and their importance, and infections which may be transmitted to rescue dogs;

7. markets, stables, slaughterhouses, refrigerators, deposits and other facilities connected with animal husbandry and the animal industry;

8. presence of animal infections important for humans and animals in cases of emergencies - rabies, brucellosis, cystic echinococcosis, etc., with special attention to epidemic infections, even if not zoonoses, such as Rift Valley fever, foot-and-mouth disease, hog cholera, sheep pox, avian influenza;

9. vectors, their seasonal occurrence, grade of nuisance and infections transmitted - e.g. zoonotic leishmaniasis, blue tongue;

10. wild and synanthropic animals, especially those that may cause problems in refugee camps - rodents, snakes, scorpions;

11. slaughterhouses, refrigerators and deposits where deteriorated materials may be present in cases of disaster and create environmental problems;

12. places and facilities to destroy carcasses and deteriorated materials;

13. possible refugee camps, location and organization (collaboration in);

14. facilities for hosting animals involved in emergencies;

15. roads and other means of communication;

16. equipment for transport of animals and materials;

17. diagnostic laboratories and professionals available;

18. slaughterhouses, dairy plants and other facilities in or close to the area;

19. industrial and nuclear plants which may be a cause contamination;

20. civil defence, other agencies and non-governmental organisations involved in the management of emergencies; and

21. connection with the alarm system (if existing) in case of disaster.

CONTROL OF ZOONOSES

The possible impact of a single zoonosis varies with the type of emergency and the situation. The following aspects should be considered.

1. Disasters do no create zoonoses and other communicable diseases. Infections already present in the area may emerge. Also the import of infections from other areas may be facilitated by the traffic of animals, food and merchandise.

2. The assemblage of people and the contacts with domestic, synanthropic and wild animals that follow many disasters, may favour zoonotic infections.

3. People involved in disasters are often debilitated. Children, immunocompromised and sick people are part of this population.

4. Living and food habits are changed, with difficulties of adaptation.

5. The provision of food and lodging for the human population involved is always a problem, and requires attention for safety and supply. Sometimes the rescuers may also cause difficulties.

6. Feeds and quarters available for domestic animals may be insufficient and force the use of unsafe substances and/or locations.

7. The population may be exposed not only to classical zoonoses, but also to other animal-connected problems, such as environmental and food contamination involving animals and food of animal origin.

8. Special problems may be connected with bites (dogs, cats, etc.), attacks from bees and other insects, etc.

9. The study of veterinary action in disasters (veterinary disastrology) is a new science; consequently there is little information on the connections between disasters and zoonoses.

RABIES

Rabies is present in many areas and involves mainly dogs, but also other carnivores and bats. Disasters may break the human-dog link and interrupt stray dog control, if existing. Humans are obliged to abandon their residences and are more exposed to contact with animals. Dogs tend to become vagrant and are exposed to contact with rabid subjects, if present. A special way of exposure may come from the use of dogs as human food, both customary and dictated by necessity. Human exposed to bites or contacts may not find appropriate treatment. Another infection that may be linked to contact with infected dogs in uncontrolled situations is cystic echinococcosis. While rabies in humans is manifested in a short time, hydatidosis requires a long time and may not be considered a problem worth taking into account at the moment of emergency. Stray dogs may constitute per se an important problem, independently from dog-transmitted zoonoses.

BRUCELLOSIS

Brucellosis in domestic ruminants of an infected area causes a series of problems. If its presence in the area is not known, it may be the cause of a human disease falling into the "influenza complex" or the "malaria complex". The forced proximity of humans and infected animals e.g. in refugee camps, may facilitate the infection. The use of untreated milk and fresh cheese is the most frequent cause of human infection. Forced mixing of Brucella-free and infected herds may disseminate animal brucellosis. Similar mechanism may cause the transmission of Q fever, which receives less attention than brucellosis.

FOOD-BORNE ZOONOSES

People facing an extreme disaster may be obliged to use contaminated food and/or water to avoid starvation. Consequently they may be exposed to infections or intoxications from ingesting meat from animals that have died or that were sick when slaughtered, or to cholera and hepatitis from contaminated seafood. In such a situation the sole solution is the provision of normal food and water. Problems may come from the use of untreated milk and insufficiently cooked meat. Brucellosis, salmonellosis, taeniasis, trichinellosis and other infections may be spread in these cases. The improvised field slaughtering of animals by non-professional persons without veterinary assistance is dangerous for the consumer and may transmit infections to operators, such as anthrax, erysipelas, Rift Valley fever, glanders, rabies, dermatomycoses, ticks and others. The preparation and distribution of food to refugees, especially in camps, requires the skills of mass catering, paying attention not only to health problems, but also to food provision and local customs. Generally, veterinarians are responsible for all food, not only for that of animal origin.

ARTHROPOD-BORNE ZOONOSES

Many factors facilitate the transmission of arthropod-borne zoonoses in cases of disaster. People may be obliged to live in the open air. Usual precautions are not practicable, and protective tools may not be available. Seasonal factors may favour, or not, the multiplication of arthropods. Some disaster, especially floods, may cause a multiplication of arthropods, while other, such as drought, may be an obstacle. Of the long list of arthropod-transmitted zoonoses we will mention leishmaniasis, Rift Valley fever, West Nile fever, and many forms of encephalitis. In places in which bat-transmitted rabies is present, the exposure of humans to bats consequent to disasters may create a situation comparable to arthropod transmission.

EXPOSURE TO CONTAMINANTS

Some environmental contaminants such as chemicals (e.g. dioxin) and radiations may pollute animals and be found in their products (meat, milk, eggs, honey). Disasters involving marine and fresh water environments may contaminate fish and other food. These contaminations are a danger for human health, especially if not detected and counteracted. In many cases they are the cause of major economic losses. In some instance the area involved is unsuitable for animal farming (or exploitation of aquatic environments) for a long period.

CAPACITY BUILDING FOR SURVEILLANCE AND CONTROL OF ZOONOTIC DISEASES IN URBAN AREAS

Giovanni Poglayen

The cultural revolution in zoonoses approach marked by the birth of veterinary urban hygiene (VUH) is already 28 years old and going to reach full maturity. After the classification of urban areas (a concept that does, however, vary greatly in different countries), and of the environments and the categories of animals they harbour, different zoonoses were classified according to their epidemiological patterns: zoonoses with an urban cycle; zoonoses derived from environmental "animalization"; zoonoses transferable from the rural habitat and vice versa; and, finally, imported zoonoses. A strong network of technical support was thus established for the evolution of those problems that over the past decades were brought to the attention of veterinary public health in urban areas. The evidence of maturity came with the most recent definition of VUH that reads: "The complex of activities of veterinary competence able to promote human health in the urban environment". Here, the term "health" is not defined as the mere absence of disease, but is given a positive meaning as "a state of complete physical, mental and social well-being". Both definitions are synergetic ally summarized in the concept of zoonoses, which are now considered not only diseases naturally transmitted from animals to man but as "any detriment to the health and/or quality of human life deriving from relationships with (other) vertebrate animals or edible or toxic invertebrates". The interpretation of the new concept is both enlightening and revolutionary in that zoonoses now embrace all problems (whose seriousness depends on the sensibility of communities and individuals) associated with the presence of animals in the urban environment. Actually, a definition seemingly so far from the original concept stresses a series of tasks and activities that over the past three decades have been accumulating all over the world, identifying new responsibilities for public veterinary action in urban territories. It can be affirmed that VUH reached its maturity with the transition from biological risks to problems. This means that instead of speaking of dermatomycoses, leishmaniasis, toxocariasis (still representing major zoonoses with an urban cycle), issues were tackled such as animal populations management in towns, faecal pollution of the environment, and cat and dog straying or vagrancy. These are all problems whose impact in term of pathologies is less than the nuisance caused by the situation itself and that are magnified by the media.

The increasing power of the media is certainly another challenge to veterinary services, which are usually ill-prepared to show full transparency in their activities, as is required by global communication. These communication problems affecting the veterinary category are further compounded by sensationalism and by poor preparation sometimes produced by the media as a sort of "jam" purposely spread over a public that has by now become aware and culturally capable of correctly understanding even distorted information. In the absence of official communication structures and of a specific task force, this trend appears hard to counteract, and the problem is exacerbated by the poor visibility of veterinary activities in general, and of the social service they provide. With some variation, these problems involve all countries and their magnitude depends upon the efficiency of veterinary services (which is in turn linked to the resources invested in the health sector). For example, some nations that during the cold war had an excellent and all-reaching health service organization were later to face issues associated with massive urbanization, besieged by shantytowns not only in the suburbs but also in the city parks. A dramatic rise in the stray dog population with resulting attacks on people and the reappearance of urban rabies were contrasted with the increased sensibility of the public to animal well-being and, as a result, by their reluctance to accept drastic measures of dog population control. Old problems (rabies, dog straying) are counterbalanced by a new feeling (the animal rights movement) that profits from a globalized pietism spread by the media; some Italian television programmes were broadcast with this very sense originating a paralyzing chain of animal-lovers' solidarity. The result was a waste of resources in neutering campaigns; these were not supported by ecoepidemiological data that would have allowed this intervention to be properly planned and evaluated. The concept of euthanasia, which has always existed as an instrument of veterinary profession, now meets with strong opposition even on veterinarians' part, whereas its extension to human beings is winning increasing favour as a precondition for its liberalization in the near future.

Along with a greater attention to the welfare of animals, the tendency has grown to transform them into objects whose possession does not represent a complement to affection but an instrument of social prestige. From this secularization of animality - an antithesis since animal shares the same root with the Latin word anima, soul - stems the phenomenon of keeping more and more exotic pets. This has health consequences such as fatal encephalitis in children following infection with raccoon ascarids, and, most importantly, dog bite emergencies caused by aggressive canine breeds. The animals may then be abandoned or kennelled. The problems associated with the management of kennels are so far from being solved that to date not even a minimum level of well-being has been established for captive animals. Similar problems are encountered in the animal trade and pet shop such as impoverishment of planetary resources with risk of extinction of some species (e.g. parrots) and the introduction of exotic pathologies through aquarium plants (mycobacteriosis, schistosomiasis). Following the elimination of many customs barriers, the frequent movements of our animals call for strict control and reliable certifications. In Italy alone, starting from 1980, leishmaniasis has already become endemic in the whole country including some (ecologically) unsuspected alpine areas. This has been caused by the coming and going of dogs from southern endemic foci.

In addition, the epochal migrations experienced by industrialized countries have introduced food habits, customs and traditions leading to the re-emergence of typically rural zoonoses in urban districts; indeed, foci of cystic echinococcosis and taeniasis in the USA were ascribed to settlements of Hispanics coming with their animals from the southern areas of the continent. Also the use of animals has changed, ranging from "pet therapy" to psychological support in prisons and hospitals, and from education in schools to the employment of animals in civil defence. Each of these tasks commands different, stringent health standards as well as aptitude evaluation of the man-animal relationship. In this context, some valuable help can be provided by behavioural medicine, a novel specialized branch of veterinary activity. Besides a wider worldwide circulation of contributions and VUH experiences, the challenge faced in the third millennium by this new branch of public veterinary activity is willingness to cooperate with other professional categories.

Physicians and biologists are certainly culturally allied figures; the former, with their data bank on human health, may give invaluable contributions to the management of animal-associated problems and, at the same time, benefit from data on animal pathology they may use, for instance, for assessing risks of exposure to certain carcinogenic agents. Biologists have become indispensable in ecological evaluations needed to manage synanthropic animal populations, occasionally including urbanized wild species. Conceptually more distant is collaboration with engineers, architects and town planners, categories able to work out building solutions for cities and dwellings to make them suitable also for animals. Some few relevant examples are green areas, public and household toilets for dogs and cats, automatic systems of faeces disposal, synanthropic animal-proof buildings.

A safe man-animal coexistence is now an integral part of modern society and its attainment calls for a strong commitment of public veterinary services not only in terms of economic resources, but also of intellectual, imaginative and inventive skills for the realization and control of means and instruments of health management in the broadest sense of the terms.

Thanks are due to Professor Giorgio Battelli for contributing ideas and remarks.


[9] Dipartimento di Sanità Alimentare ed Animale.
[10] WHO/FAO Collaborating Centre for Veterinary Public Health, Dipartimento di Sanità Alimentare ed Animale, Istituto Superiore di Sanità - Rome.
[11] Dipartimento di Sanità Alimentare ed Animale.
[12] Dipartimento di Sanità Alimentare ed Animale.
[13] Dipartimento di Sanità Alimentare ed Animale.
[14] Centro Regionale Epidemiologia Veterinaria, Istituto Zooprofilattico Sperimentale delle Venezie, Padova.
[15] Dipartimento di Sanità Alimentare ed Animale.
[16] Italian Department for Civil Protection Health and Environment Office.
[17] Dipartimento di Sanità Pubblica e Patologia Animale, Università di Bologna, Italy.
[18] Dipartimento di Sanità Alimentare ed Animale.
[19] WHO/FAO Collaborating Centre for Veterinary Public Health, Dipartimento di Sanità Alimentare ed Animale, Istituto Superiore di Sanità - Rome.
[20] WHO/FAO Collaborating Centre for Veterinary Public Health, Dipartimento di Sanità Alimentare ed Animale, Istituto Superiore di Sanità - Rome.

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