Early warning mechanisms en able rapid detection of the introduction of or sudden increase in the incidence of a serious disease such as FMD before it develops to epidemic proportions and causes serious socio-economic consequences. The mechanisms embrace all initiatives, mainly based on disease surveillance, reporting and epidemiological analysis, that lead to improved awareness and knowledge of the distribution and behaviour of disease outbreaks (and of infection) and that allow forecasting of the source and evolution of disease outbreaks and monitoring of the effectiveness of disease control campaigns.
The success of a country's capability for rapid detection of introduction or increased incidence of FMD depends on the following:
good farmer and public awareness programmes for FMD and other high-threat epidemic livestock diseases, which involve improving the veterinary/farmer interface;
training of field veterinary officers (FVOs), veterinary auxiliary staff, private veterinarians, agricultural extension officers, local authorities and livestock owners in the clinical and gross pathological recognition of FMD and other serious epidemic livestock diseases; collection and transportation of diagnostic specimens (in the case of veterinary staff); and the need for prompt action;
sustained active disease surveillance, to supplement and improve passive monitoring based on close coordination among livestock owners, field and laboratory/epidemiology veterinary services, and the use of techniques such as participatory epidemiology techniques, serological surveys and abattoir monitoring to supplement field searching for clinical disease;
dependable, rapid emergency disease reporting mechanisms to regional and/or national/federal veterinary headquarters;
implementation of an emergency disease information system (such as the Transboundary Animal Diseases Information System [TADInfo]);
enhancement of laboratory diagnostic capabilities, sample collection, and dispatch for FMD within provincial and national veterinary laboratories;
development of strong linkages between national laboratories and regional and world reference laboratories;
strengthening of national epidemiological capabilities to support emergency preparedness and disease management strategies;
prompt and comprehensive international disease reporting to OIE by all countries and particularly to regional animal health organizations;
close liaison with veterinary authorities in neighbouring countries both at a national level and at a local level near shared borders.
It is beyond the scope of this manual to discuss the above issues in any detail. For more information, reference should be made to the Manual on the preparation of national animal disease emergency preparedness plans (FAO Animal Health Manual No. 6) and the Manual on livestock disease surveillance and information systems (FAO Animal Health Manual No. 8). However, a few of the most important issues for FMD early warning preparedness will be described below.
In many countries it is likely that very few veterinarians or other animal health workers in either the public or private sector will have had any direct, first-hand experience with FMD or other transboundary animal diseases, as these diseases may never have occurred in the country or have been exotic for a considerable period. If FMD is rated as a high-threat disease, this deficiency needs to be rectified by a systematic training programme for all those people who, in their professional capacity, may possibly be the first to come into contact with an incursion or outbreak of the disease. Because a disease may strike in any part of the country and because of staff turnover, training programmes should be both comprehensive and regular. Training must extend to staff in the remotest parts of the country, as well as to selected officials (agricultural extension officers, local authorities) and livestock owners.
In other countries where FMD may be endemic, complacency as to the occurrence of the disease must be overcome if efforts are truly to control the disease progressively. It must be a desired outcome by all parties: private and public. In training sessions, the shared benefit of FMD control must be underlined and the critical nature of the country's investment for the public good understood.
Obviously, it will neither be practicable nor necessary to train personnel to a high level of expertise in these diseases. In most cases it is sufficient that trainees be at least familiarized with the basic clinical, pathological and epidemiological features of FMD and with what they need to do if they suspect one of these diseases. Perhaps the most important thing to inculcate in people is an attitude of mind - if they are confronted by an unusual disease outbreak involving foot-and-mouth lesions in ruminants or swine, they should include FMD in the range of their differential diagnostic possibilities and act accordingly and immediately. They should be trained in the steps that they need to take to secure a confirmatory diagnosis, including collection and transport of diagnostic specimens, and in the immediate disease control actions that need to be instituted at a disease outbreak site. More specialized training will be needed for those personnel who are nominated as members of specialist diagnostic teams (see section on the Specialist diagnostic team on p. 35).
A number of training possibilities may be selected, as appropriate. These include:
Sending key field or laboratory staff to another country to gain first-hand experience when there is an FMD outbreak there, or making use of any other opportunities offered for field and laboratory staff to profit from the experience of countries in the process of controlling an outbreak (e.g. by attending workshops).
Other international training opportunities that may occur from time to time. Several countries with access to microbiologically high-security laboratory and animal facilities run training courses in which exotic diseases can be demonstrated by experimental infection of susceptible livestock species. These courses are run in countries such as Australia, the United States, the United Kingdom and South Africa and there are opportunities for external students to attend. There is also the possibility for laboratory staff to be trained at world or regional reference laboratories; training programmes may also be arranged occasionally by other international organizations. During project (assistance) proposals, participation in these courses should be budgeted.
National emergency disease training workshops, which should be organized as the mainstay of training and be targeted at government field and laboratory veterinary officers, public health and quarantine veterinarians (including those stationed at abattoirs, markets, border posts, airports and seaports), veterinary practitioners, and industry veterinarians. Ideally, these workshops should include representatives from neighbouring countries, and should filter down, by means of workshops organized by those who have been trained, to farmer level.
Field diagnostic manuals, which are most useful if they are prepared in a simple, practical and graphic format whereby they can always be carried in a vehicle and be available for quick reference at the site of a disease outbreak.
These programmes form part of the most critical, but sometimes neglected, aspects of preparedness planning for emergency diseases, and for fostering "ownership" of and support for emergency disease control/eradication campaigns by livestock farmers, community leaders, and other key stakeholders. They also engender a bottom-up approach to planning and implementation of disease control programmes, to complement the more traditional top-down approach adopted by governments.
Communication strategies should aim to make stakeholders aware of the nature and potential consequences of FMD and other important livestock diseases and of the benefits to be derived from their prevention and eradication. Furthermore these strategies should always have an element of rallying the community to the common cause of preventing and fighting a disease epidemic, ideally resulting in farmer sanitary defence groups and farmer organizations.
One of the important messages to get across is that it is essential to notify and seek help from the nearest government animal health official as soon as an unusual disease outbreak is seen in ruminant animals and pigs. Publicity campaigns should not only be directed towards farmers but also towards local authorities and livestock traders.
One of the more delicate aspects of notification of a suspect case of FMD or other highly infectious disease in an animal population is the perceived repercussions this may have on the individual reporting the case. Confidentiality must be preserved if the report is exposing someone else's livestock, and appreciation and gratefulness exemplarily shown if people report disease occurrence in their own animals.
Livestock traders, dealers and marketers are essential target groups for public awareness campaigns and are often overlooked. The movement of animals through livestock traders is often the key epidemiological factor in the spread of FMD and other epidemic livestock diseases. The need to build up a climate of trust and confidence between animal health officials and livestock traders is as important as that discussed for farmers. The general themes for emergency disease awareness should also be similar although emphasis should be placed on the importance of doing the "right thing" about sourcing animals from disease-free areas where possible; not buying any sick stock; following rules about quarantine, vaccination, testing or identification of animals; and keeping records. The potential consequences of the occurrence of a disease on internal and international trade should be emphasized.
It is recommended that a specialist FMD diagnostic team (or teams) be nominated within a country so that the team can be immediately mobilized when there is a report of a suspect outbreak of vesicular disease from the field. These arrangements should be made well in advance of any emergency. Members should be avail-able, prepared and equipped to travel to a disease outbreak site at short notice. The site should have all the equipment needed for the preliminary investigation of a disease, for collection and transport of diagnostic specimens, and for rapid and immediate communications.
The composition of the diagnostic team will vary according to circumstances, but could include:
a veterinary pathologist from the central or regional veterinary diagnostic laboratory;
a specialist epidemiologist, preferably with first-hand experience or training in FMD;
a veterinarian with extensive experience of endemic diseases in susceptible livestock species;
any specialist required for specific examinations.
If there are people with expertise in more than one of the above areas, the size of the diagnostic team can be reduced accordingly.
The team would travel to a disease outbreak site with local veterinary staff if so directed by the chief veterinary officer (and would be provided with the transport to do so). The specialist diagnostic team should seek local authority assistance (e.g. community elders, agricultural representatives and local leaders) to facilitate subsequent actions.
The specialist diagnostic team would be expected to:
make clinical examinations;
make preliminary epidemiological investigations, particularly with regard to tracebacks (have any new animals joined the infected herds in the last four weeks and where did they come from?) and traceforwards (have any animals left the infected herds in recent weeks and where did they go?);
collect a range of diagnostic specimens both specifically for FMD and for any endemic or exotic diseases that might be included in the differential diagnosis and transport these back to the laboratory.
The team should also have the authority to take immediate disease control actions that are necessary at the outbreak site. They should be empowered to provide any immediate instructions to local animal health officials.
The team must report back immediately to the state/provincial/ regional veterinary officer and the CVO on their assessment of the situation, including steps taken to secure a confirmatory diagnosis. They should also advise on further disease control strategies, including declaration of infected and surveillance zones, any necessary measures to improve disease reporting from the outbreak area and the desirability of setting up a local disease control centre.
The rapid and certain diagnosis of diseases can only be assured in fully equipped laboratories with a range of standardized diagnostic reagents, experienced staff and a sufficient throughput of diagnostic specimens to maintain expertise. Additionally, the development of diagnostic expertise for exotic diseases for tests that require handling the live agent should only be attempted in microbiologically high-security laboratories.
It would therefore be impractical and excessively costly for most countries to maintain a national veterinary diagnostic laboratory with full capabilities for confirmatory diagnosis of all transboundary and other emergency diseases, many of which will be exotic. However, it is to be expected that at least those countries with significant livestock populations will have a veterinary diagnostic laboratory that is equipped and competent to undertake a broad range of standard techniques in pathology, virology, bacteriology and serology to the level where preliminary identification of aetiological agents for most, if not all, emergency livestock diseases can be attempted. If FMD is deemed to be a very high-threat disease, consideration should be given to developing capabilities for some primary key diagnostic tests, e.g. ELISA tests for both antigen and antibody detection.
Specimen transport containers with transport media should be kept at both central and state or provincial veterinary laboratories and should be made readily available for FVOs and specialist diagnostic teams. These containers should ideally be leakproof primary containers such as glass or plastic universal bottles with a screw top and rubber washer, or good-quality plastic screw-top jars. These are then packed into a leakproof secondary container with absorbent material and an ice pack to keep specimens fresh. This is finally placed into a robust cool box or other container with good labels. Specimen advice notes should also be provided (see Chapter 2, Diagnosis on p. 16). Copies of all details dispatched should be documented.
A network of FAO and OIE Reference Laboratories and Collaborating Centres exists for FMD around the world and is available for providing advice and assistance to countries. Names, full contact details, subjects and geographic areas of responsibility are given in the Appendix.
As part of their FMD contingency planning, countries should establish contact and a dialogue with the appropriate reference laboratories and collaborating centres. Countries should determine the nature and range of diagnostic specimens or isolated agents to be sent for confirmatory diagnosis or further characterization; any transport media to be added; method of packaging and refrigeration; labelling of package, including correct address; and any necessary customs or International Air Transport Association (IATA) declarations. This information should be documented in the emergency preparedness plans.
It is very important that potential or confirmed aetiological agents from emergency disease outbreaks be sent to the appropriate international reference laboratory for further characterization. It is recommended that several isolates from different geographic locations and at different phases of the outbreak be forwarded. Submission of samples to any laboratory outside the country of origin should always be subject to prior agreement with the recipient and be transported in containers meeting IATA regulation standards.
Full use of reference laboratories and collaborating centres should also be made for the help that they can provide in training opportunities, provision of specialized advice and standardized diagnostic reagents.
It is particularly important for countries that are employing FMD vaccination programmes to engage as a matter of routine in disease surveillance activities that will provide early warning of any changes in the FMD serotypes or subtypes circulating within the country. Indicators of this might be a sudden upsurge in the incidence of the disease or the occurrence of vaccination breakdowns. Such occurrences should be immediately investigated and diagnostic samples collected for virus characterization.
Vaccinating countries should also routinely collect representative field samples of FMD virus strains from all outbreaks and representative areas in the country at least once or twice a year and send them to an international reference laboratory for strain characterization. This will ensure that the most appropriate vaccine strains can be selected for use in the country and the epidemiological evolution of the disease can be tracked.