This document was produced by MAFF as a specific response to the FMD outbreak in the UK in 2001 and was made available on their website. Risk Assessments and specific recommendations related to the conditions in the field at the time and should be viewed in this context as they may not be applicable to outbreaks occuring under different circumstances.
Foot and mouth disease
9 April 2001

MAFF: Veterinary Risk Assessment No.8: What is the risk of causing new outbreaks of fmd if animals are slaughtered and their meat and waste products are distributed through the normal channels?

1. Summary of risk factors identified in full assessment.

Moving livestock to an abattoir (whether direct, or via a collection centre) during an FMD outbreak increases the risk of spreading infection to premises which were previously uninfected. The greatest risks are to the premises of destination, that is the locality of the lairage and abattoir and, if utilised, any collecting centres. There are lower risks to the premises of origin and premises passed during the journey. Once slaughtered, there are risks associated with the distribution and use of the products of slaughter, which vary with the use and level of processing. The factors considered to be most responsible for increasing the risks are:

• Failure to detect FMD infection at premises of origin
• Failure to take account of recent history of all animals at the premises of origin
• Failure to take account of recent history of animal transport vehicle and equipment
• Lack of awareness of appropriate hygienic precautions
• Failure to disinfect vehicles and equipment
• Failure to quarantine animals following suspected contact with FMDV
• Failure to quarantine personnel following suspected contact with FMDV
• Failure to minimise distance, time travelled, and stopping points on route
• Movement of livestock or vehicles from infected areas to apparently unaffected areas
• Close proximity of an infected premises to route/journey

• Failure to site lairage, abattoir and any collecting centre away from susceptible livestock
• Failure to use all-out batch systems at lairage, abattoir and any collecting centre
• Failure to minimise time in lairage and any collecting centre
• Failure to detect infection at lairage, abattoir and any collecting centre, and failure to take appropriate measures if infection detected
• Failure to disinfect premises and equipment between batches
• Failure to utilise dedicated personnel, appropriate hygiene and quarantine
• Failure to minimise aerosol production at slaughter
• Failure to ensure perimeter security and appropriate adequate containment of facility
• Failure to ensure adequate and appropriate waste disposal methods, including the use of slurry, disinfectant, sealed transport and siting of waste disposal away from susceptible livestock

• Failure to ensure external disinfection of vehicles
• Failure to consider removal of potentially high titre tissues and treat as waste
• Failure to disinfect product if/where possible
• Failure to sterilise product if/where possible (e.g. pig-swill, MBM)
• Failure to utilise appropriate hygiene precautions to reduce cross-contamination
• Failure to ensure appropriate disposal of raw waste
• Failure to educate consumers wrt appropriate disposal of meat products

• Failure to detect clinical infection at any stage
• Failure to minimise time in lairage and at any collection centre
• Failure to site lairage, abattoir, and any collecting centre away from susceptible livestock
• Failure in waste disposal procedures at any stage

1. Ensure that vehicle, equipment and driver do not introduce infection to farm of origin.
2. Ensure that there is no evidence of clinical infection in animals on the farm of origin (it is impossible to be sure that none are incubating FMD).
3. Minimise distance travelled and time between departure and arrival.
4. Ensure that any affected animals are detected before being slaughtered (or, if collection centre or market used, before onward movement to slaughterhouse).
5. Differentiate between pigs and other species because of their greater potential virus excretion.
6. Ensure that animals are killed as soon as possible after leaving the farm (by end of following day at latest), to prevent any possibility that animals infected in transit, at collection centre or market, or awaiting slaughter at abattoir, can themselves become infectious.
7. Ensure cleansing and disinfection of vehicles at delivery site, immediately after unloading.
8. Ensure safe handling and disposal of by-products that are not intended for human consumption.
9. Ensure that staff at collection centres, markets or slaughterhouses do not spread infection to susceptible livestock elsewhere.

1. No action is entirely without risk, but a policy which prevents any livestock being moved anywhere for any purpose is practicable only for a limited period of time. If movements are to be permitted, then movements of clinically healthy animals for slaughter carry the least risk, though it is possible that some may be infectious but not clinically affected, and even that some of these will develop lesions after leaving the farm and before being slaughtered. Such movements do not permit indirect spread of infection via contact animals as long as these are all killed within 48 hours of contact occurring.
2. Movements may originate from:
• farms in Provisionally Free Areas
• farms in At Risk Areas
• farms in Infected Areas situated more than 3km from an Infected Premises
• farms situated within 3km of an Infected Premises
3. Movements may be:
• direct from farm to slaughterhouse
• direct from farm to a licensed collecting centre, and thence direct to a slaughterhouse, or
• direct from farm to a licensed slaughter market, and thence direct to a slaughterhouse.
4. Unrecognised infection is most likely to be present on farms within 3km of an Infected Premises, and least likely on farms in Provisionally Free Areas. However, provided that animals are slaughtered within 48 hours of leaving the farm, and that vehicles are clean and disinfected before use and immediately after unloading, the risk from any of these types of movement is low, though greatest for markets and least for direct movements from farm to slaughterhouse. The greater risk at markets is associated with the mixing of animals, farmers and others who have handled livestock, leading to contamination of clothing and footwear and indirect transmission of infection to susceptible livestock elsewhere.
5. Animals of any species should be licensed direct from a farm to a slaughterhouse subject to the following conditions:
• livestock vehicle to be clean and disinfected before entering farm to collect animals
• animals on farm, including those to be slaughtered, to be certified free of clinical signs of FMD immediately before loading. Ideally this should be certification following a veterinary inspection, but owner declaration is an acceptable alternative in Provisionally Free and At Risk Areas if the other precautions which are recommended are implemented. Veterinary inspection before movement from farms in Infected Areas is essential.
• movement to be licensed and completed on day inspection made or declaration signed.
• movement to be direct, with no multiple pick-ups, to destination which can reasonably be reached within 4 hours.
• animals must be slaughtered within 24 hours of arrival at the abattoir, and must not be sent there without an assurance that this can be done.
• vehicle must be cleaned and disinfected under official supervision after unloading and before leaving the slaughterhouse.
• any material produced at the slaughterhouse which is unfit for consumption must be handled and disposed of by a method which prevents transmission of infection to animals.
6. Cattle and sheep - but NOT pigs - could also be licensed to move from the farm to a licensed collecting centre, from which movement would be direct to the slaughterhouse. The additional stage implies a slightly increased, but still acceptable risk, provided that:
• the collecting centre is licensed to operate under conditions which ensure that animals still reach the slaughterhouse on the same day they left the farm of origin, which preclude the build up of infection on the premises, and which prevent inadvertent transmission of infection to susceptible livestock either by personnel or equipment.
• collecting centres should operate under official supervision.
• all animals should leave the centre on the day they arrive there, and arrive at the slaughterhouse on the same day they left their farm of origin.
• the centres must be emptied of all livestock before the end of the each day, and be cleaned and disinfected before being used again
• delivery vehicles must be cleaned and disinfected under official supervision immediately after unloading and before leaving the site.
7. The conditions listed at 3(v) are also applicable.
8. Markets carry a greater risk because the mixing of animals and people is less easily controlled. Slaughter markets should not be licensed, even in Provisionally Free Areas, at this time.
9. Slaughterhouses and collecting centres can be approved and licensed in infected and or in controlled areas.
10. All movements should be to premises situated in the same or in a higher risk category area. Animals from farms in an Infected Area must be slaughtered within the same, or in a contiguous Infected Area. Animals from farms in At Risk Areas may be slaughtered in that area, or in an Infected Area: they may not move to a slaughterhouse in a Provisionally Free Area.
11. Safe disposal of animal by-products, including manure and slurry is already controlled by the 1983 Order, as amended.

Contributors:

Dr A I Donaldson IAH Pirbright Laboratory
L Gallagher Risk Research Dept, VLA, Weybridge
Dr L Kelly Risk Research Dept, VLA, Weybridge
Dr P Kitching IAH Pirbright Laboratory
C T Livesey Risk Research Dept, VLA, Weybridge
K C Taylor Veterinary Consultant
Dr M Wooldridge Head of Risk Research Dept, VLA, Weybridge