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This paper was presented at RBI/EAAP/FAO meeting in Budapest on 23 August 2001

Foot-and-Mouth Disease in the United Kingdom 2001; its cause, course, control and consequences

Lawrence Alderson

Rare Breeds International, 6 Harnage, Shrewsbury, Shropshire SY5 6EJ, UK alderson@clltd.demon.co.uk

Summary

The epidemic of Pan-Asian 'O' type FMD in 2001 was the first major outbreak in UK for 34 years. The cause is not understood at this time, but it spread rapidly through many areas. Discrepancies between official and unofficial statistics impede a clear understanding of the development of the disease, but probably up to 10 million animals were slaughtered during the first five months. Control measures relied on mass slaughter, but the slow initial response allowed the disease to become widespread. Expert opinion criticised the control measures and advocated the use of vaccination, and the legality of the control measures was challenged. The cost of the outbreak is estimated in the region of £20 billion, and may be increased by future compensation claims. The impact on the livestock industry in UK has been severe.

The reduction in numbers of livestock coincides with Government policy and may be permanent, and the damage to animal genetic resources has been significant.

There are demands for a public inquiry to define the systemic failure of the control measures, and a review of methods of livestock production and marketing to re-evaluate the benefits of local production.

Keywords: Foot-and-Mouth disease, slaughter, vaccination, genetic resources

Introduction

Foot-and-Mouth disease (FMD) first appeared in Britain in 1839, and was made a notifiable disease in 1871. It occurred with some regularity up to the 1950s and there was a minor outbreak in 1981, but the last major outbreak was in 1967 when it was concentrated mainly in the north-western region of England and 442,000 animals were slaughtered. The 2001 outbreak was officially recognised in February, and became widespread through many parts of the United Kingdom (UK), being particularly severe in Cumbria, the Scottish Borders, Devon and County Durham, with later severe outbreaks in the Pennine Dales of Yorkshire and Lancashire, Cheshire, Somerset, South Wales and other areas.

Although the effect was particularly devastating in some areas, it had a serious effect on the whole livestock industry which still had not recovered from a series of earlier problems, such as salmonella, swine fever, e coli and BSE.

The problem was not restricted to those farms with infected animals, or to neighbouring farms. Large areas were subject to movement restriction orders, and farms in these areas were burdened for an extended period with the costs of feeding and maintaining animals intended for sale, at the end of which time the animals usually were beyond a reasonable selling age or weight. No account of this category of loss has been included in any analysis or figures relating to the FMD outbreak.

The effect of untreated FMD varies according to strain, but is mainly short-term and expressed through reduced production. The Department of Environment, Food and Rural Affairs (DEFRA), formerly the Ministry of Agriculture, Fisheries and Food (MAFF), advise that 10% deaths may be expected with pigs and cattle, 80% will recover, and 10% show no clinical sign of the disease. The current 'O' type appears to be more virulent in cattle and pigs, but the effect on sheep is very mild and only young lambs are likely to die.

FMD is covered by European Union (EU) rules. Community rules are set out in Council Directives 85/511/EEC and 90/423/EEC, and restrictions on movement (i.e. export to other member states) are dealt with in Directive 64/432/EEC (as amended by 89/662/EEC). Article 4a prohibits intra-community trade in animals: "from a Member State which has, during the previous 12 months, practised prophylactic vaccination or has had recourse, in exceptional cases, to emergency vaccination on its territory." However, the EU Court of Auditors reported in 2000 as follows: "The Community's non-vaccination policy - - - is called into question by the development of marker vaccines, and the very high costs associated with the 1997-8 epidemic (of swine fever). The Commission should update its cost-benefit analysis." Now it seems likely that a proposal will be made at the November 2001 summit that vaccination without slaughter should become EU policy.

Rules for the conduct of international trade in respect of FMD also are set out in the "International Health Code - 2000" (chapter 2.1.1.) published by the Office International des Epizooties (OIE) (World Organisation for Animal Health) in Paris. FMD occurred in several other countries during the UK/2001 outbreak. The 'O' type occurred in Turkey, Saudi Arabia, Kuwait, Qatar, Kazakhstan and Mongolia, and the 'A' type in Argentina, Uruguay, Bolivia, Brazil, Colombia and Venezuela.

Cause

The cause of the UK/2001 outbreak must remain speculation for the time being. Various hypotheses have been promoted, including imported meat, imported wild deer, eco-terrorism, viral escape from FMD research animals, and loss of viral material from laboratories, but as yet there is insufficient firm evidence to enable causation to be ascribed. This may be established by an appropriate inquiry.

The activity of the Pan-Asian 'O' type virus, which was the causal agent of the outbreak, had been noted for some time, and the UK Government had been warned by many FMD researchers as early as 1998 to expect an outbreak of this type.

Course

Development

The disease was identified first in an abattoir in Essex on 20 February in pigs from a farm in Northumberland. It developed rapidly from the third week to the eighth week (Figure 1) with its peak of growth in the sixth week when up to 50 new infected farms were recorded daily. Thereafter the number of daily new cases declined, but the true situation became increasingly obscure as a result of changes in reporting procedure after 28 March which had the effect of artificially reducing the number of cases recorded.

Four categories of farm were recognised, namely infected farms (IP), contiguous farms (CP), other dangerous contact farms (DC) and 'slaughter on suspicion' (SOS) farms. In early May official figures ceased to include CP, DC and SOS farms. The figures were further depressed as veterinary surgeons began to avoid blood testing to confirm FMD, and whenever possible (i.e. if a farmer did not insist on a second opinion or blood tests) the farm was classified as SOS which did not need to be recorded publicly. Records of positive blood tests and details of new cases did not always reach the official lists as they required approval by Pirbright and a MAFF committee respectively.

The effect of these changes can be seen from figures for the weeks ending 6 May and 13 May. Official figures show the daily average of animals slaughtered as 16,000 and 9,000 respectively, but figures drawn from other MAFF information reveal that the actual figures were 30,286 and 29,714, and show no decline from the week ending 29 April. During the week ended 20 May, when officially there was only a daily average of three new infected farms, the daily slaughter had risen to 41,857 animals and again reached 35,000 animals per week at 20 July.

Figure 1

Animals slaughtered and farms infected to 20 July (day 150 of outbreak) (animals ,000s; farms actual)

By 31 May (100 days after confirmation of the first case) the official figures showed that 3,168 thousand animals had been slaughtered, but the true total was considerably higher at more than 8 million (Figure 1).

The discrepancy arose mainly because a dam and her progeny were counted as one unit in official statistics, and because animals slaughtered for welfare reasons were not included. Movement restrictions caused welfare problems which were recognised by the Livestock Welfare Disposal Scheme, and by 2 May 1,533,274 animals had been entered for slaughter.

The official figures suggest an encouraging picture of a problem under control; the true figures show an ongoing crisis.

The headline total of IP farms did not reveal the full picture. On 29 April the official figures showed a cumulative total of 1,515 IP farms, but a total of 6,612 farms had been culled.

By 20 July a total of 8,811 premises had been culled, and only 1,873 were classified IP.

The average number of adult animals slaughtered on each category of farm showed a further discrepancy (Table 1). On IP farms an average of 631 animals per farm were slaughtered compared with only 346 on other culled premises.
Table 1 Official statistics showing comparison for infected farms and other farms
Infected premises Other premises
Farms 21.2% 78.8%
Animals slaughtered 33.0% 67.0%
Adult animals slaughtered per farm 631 346

Confirmation of the unreliability of the reporting policy is seen in the number of animals slaughtered per confirmed outbreak. It rose from less than 1,000 on 13 March to almost 14,000 in late May showing the increasing proportion of farms culled without confirmation of disease. In subsequent laboratory tests, less than 20% SOS farms proved positive, and 30% of initial diagnoses of IP farms made by inspection to determine infected status did not prove positive. The overall result indicated that only a small proportion (estimated 18-25%) of culled farms were infected.

The unexpectedly long tail of the outbreak, which persisted at 4-5 new cases per day from the end of April onwards, was partly due to inadequate biosecurity measures. Public footpaths were opened prematurely owing to pressure from the tourist industry. Movement from farm to farm by milk collections tankers, contractors and farmers themselves may have contributed to spread of the disease. The failure of DEFRA officials and employees to observe necessary standards of biosecurity was recorded in many cases.

Impact on livestock

The final impact on the national breeding herd will be severe. The total population of breeding animals in the UK (as at the national census of June 2000) was circa 25 million (cattle 4.1m, pigs 0.6m, sheep 20.4m) within a total declining livestock population of circa 60 million (cattle 11.1m, pigs 6.5m, sheep 42.3m). The animals slaughtered during the first five months (circa 9.5 million) already were equivalent to maybe 16-17% of the total national population.

The effect on individual breeds varied widely. Rare Breeds International recognises three categories of breeds of special genetic importance. Among specially adapted breeds, Lonk and Rough Fell sheep suffered losses of more than 25% of their population.

The greatest losses were in South Country Cheviot and Herdwick sheep where more than 35% of the breeding population was slaughtered.

Among distinctive breeds, the largest flock (400 breeding ewes) of high-performance British Milksheep was slaughtered. Among rare breeds, Greyface Dartmoor sheep were most severely affected. Some respite was afforded by a proposal (27 April) to exempt from slaughter stock of special genetic importance, and both Rare Breeds International and the FAO National Co-ordinator played a major role in promoting this concept, but its value was limited by onerous bio-security conditions.

Control

Methods

The method of control of the outbreak was determined by the decision of the Government to accept the strategy presented by a biomathematical group from Imperial College, London,

which was based on a policy of slaughter of animals on infected farms within 24 hours, and within 48 hours on contiguous farms. This developed into the slaughter of animals on farms within 3 km (protection zone) of the infected farm in several regions, but a consistent policy was not applied. A system of 'D' notices was used to restrict the movement of animals. 'D' notices were served on farms within the protection zone and on any other farm which may have been exposed to infection or had any links with an infected farm, and an infected area was established within 10 km (surveillance zone) of a confirmed case. Animals could not be moved off these premises which affected circa 65,000 farms.

Subsequently, a national programme of testing for antibodies was implemented. Where positive results were shown, premises were classified as infected farms and the animals were slaughtered, and adjoining premises were classified as contiguous farms.

Speed of action

The programme was compromised by the slow initial reaction to the outbreak, and for several weeks the spread of the disease was one step ahead of the control measures. Support from the Army was not mobilised until early April. The clear advice from earlier experience was that a policy of mass slaughter is effective only if there is immediate slaughter of the animals and disposal on the infected farm.

This objective was never achieved.

Even three months after the start of the outbreak (late May) only 62% of infected premises had slaughter completed within 24 hours of notification. The delay in slaughter (days from notification to diagnosis, and from diagnosis to slaughter) permitted viral spread. On 14 April there were 568,000 animals, not including welfare cases, awaiting slaughter. The speed of response in many cases appears to have contravened article 5.2(a) of Directive 85/511/EC, which requires slaughter and safe disposal of the carcases "without delay" and with no risk of spreading the virus. The slow response is difficult to understand as there is evidence of awareness of the presence of FMD for maybe three or four months before the original outbreak, and movement of personnel and organisation of facilities and equipment before later outbreaks in local areas indicated pre-knowledge by MAFF of notification of FMD in those areas.

Expert evaluation

The strategy for control of FMD UK/2001 was discredited by FMD experts around the world, and particularly by Professor Fred Brown from USDA Plum Island Animal Disease Centre, and Dr Simon Barteling from the Netherlands, formally head of the European Community Co-ordinating Institute for Foot and Mouth Vaccines. Professor Brown and Dr Barteling were united in their criticism of the methods adopted in the control of the outbreak; they considered the blanket culling policy was based on faulty science and caused "the unnecessary slaughter of innocent animals".

In addition, experts in UK, Dr Alex Donaldson, Head of Laboratory at Pirbright, and his colleague Dr Paul Kitching, repeatedly criticised the cull policies based on biomathematical modelling by the team at Imperial College which were seriously flawed. The slaughter of animals on infected premises within 24 hours of reporting was supported, but the 48-hour contiguous cull policy had no scientific justification (Donaldson et al, 2001). The airborne transmission of the virus was very low and "the results of computer simulations showed that airborne spread of the UK/2001 strain of the FMD virus between pig herds over a distance greater than 0.1 km would require more than 100 pigs to be affected on the source farm". In addition "the simulations predict that it would require 100 cattle or sheep to be infected at source for an infectious dose to travel a distance of 0.2km and be sufficient to infect cattle. In the FMD situation in the UK, the level of clinical surveillance is such that it is unlikely that the number of infected cases in a cattle herd would be as high as 100. Furthermore, the emerging serological evidence suggests that infection has progressed slowly through sheep flocks during the UK epidemic and so there is a low probability that 100 sheep would be in the early acute phase of infection or clinical disease simultaneously." (Donaldson & Alexandersen, 2001).

It is difficult to reconcile the Government's application of a 3 km dangerous contact zone for 'O' type FMD (a disease with poor airborne transmission), with its rejection of the possibility of contamination of maize (a wind-pollinated plant) by GM maize beyond a 50-yard (0.046 km) radius.

The policy of testing for antibodies seemed equally flawed. The presence of antibodies, in the absence of vaccination, reveals previous challenge by the disease. There is a possibility that some animals may remain persistently infected (i.e. carriers) but the proportion is low, and the risk of a carrier infecting other animals is very low. Mass slaughter on the basis of a positive result for antibodies is disproportionate.

The consensus is that control of FMD UK/2001 by a policy of mass slaughter was not based on sound science, that it breached basic standards of animal welfare, that it required unethical conduct by participating veterinary surgeons, and that it had not proved effective in bringing the outbreak under control within a reasonable time (5 months after the initial confirmed case at the time of writing).

At a meeting in April 2001, OIE remained in favour of 'stamping-out' the disease and the slaughter of vaccinated animals, but recognised that "slaughter of animals and disposal of carcases pose logistical, welfare, environmental and social problems" and

opined that "vaccination is one measure that might be considered for the protection of such (at risk of infection) animals" (Office International des Epizooties, 2001).

Legality

The legality of the policy for control of FMD was successfully challenged in many areas. Under both EU and UK law, animals may be slaughtered on infected farms, but on adjoining premises only samples may be taken. The slaughter of animals on contiguous and other DC farms violated this principle, and the pressure applied to farmers to agree to contiguous cull was intense.

In early June a programme was initiated to test for antibodies through the national flock and herd. Positive results resulted in the classification of the farm as IP with the automatic application of slaughter and the identification of contiguous farms.

This was an attempt to accelerate the opening of export markets. Again, the legality of this procedure was challenged on the basis that antibodies do not pose a significant disease threat, and the policy was not rigorously or consistently applied.

In addition, there was evidence of cruelty during the implementation of the cull, but no action was taken by the Royal Society for the Prevention of Cruelty to Animals (RSPCA) until late May when MAFF were accused of being "arrogant, deliberately obstructing investigations, and breaking welfare laws". 80 cases were marked for possible legal action.

An independent public inquiry was demanded, not only by non-political interests such as the Royal College of Veterinary Surgeons, Trading Standards Institute and the Soil Association, but also by several Members of Parliament and the Chairman of the Agriculture Select Committee.

Vaccination

The preferred method of control advocated by the majority of experts included vaccination. Barteling cites successful control by vaccination of outbreaks in Netherlands (cattle only in 1952), Uruguay and Argentina (recent) and Kwazulu in September 2000. The contemporary Netherlands outbreak (2001) was eliminated by vaccination.

Modern vaccines have multi-strain (multivalent) potency, and serological tests can differentiate infection from vaccinal immunity. In UK it was agreed unanimously by the science group at a meeting in the House of Lords on 24 April 2001 that the vaccination route should have been adopted by the government.

Even the Imperial College team's model showed that 'ring vaccination' was as effective as 'ring culling' (i.e. contiguous cull) and that a 2 km extended cull zone was as effective as a 3 km cull, but they rejected both options (i.e. vaccination and 2 km cull).

The use of vaccination to protect special breeds is articulated in Council Directive 90/423 article 13.3 of the EU, and also when authorities are "overwhelmed" in the process of control, as occurred in UK in 2001. OIE also made reference to the desirability of conserving "certain rare or valuable animals" by vaccination, but in both cases the severe biosecurity conditions negate most of the potential benefit.

Optimum strategy

With a rapidly spreading disease like FMD, a realistic contingency plan for eradication, as described by Barteling, is applied in three phases: 1. Immediate slaughter; 2. Ring-vaccination to contain spread; 3. General vaccination if the outbreak is out of control. The first action will be the slaughter of animals on infected farms and adjoining premises. However, this will be successful only if more than 80% of farms that might have been in contact with the disease can be traced. The eradication team must be able to be ahead of the appearance of the disease. If this is no longer the case, new outbreaks must be followed by ring-vaccinations around these outbreaks. Finally, if it is clear that the virus is widespread throughout a whole district or country, a general vaccination of all susceptible animals must be carried out.

Disposal

There is limited viral spread from carcases, as the virus is inactivated by acidity in the carcase, but delay in disposal of carcases poses other health and environmental problems. In some cases carcases remained exposed for up to 5 weeks. For example, 431,000 carcases were awaiting disposal on 14 April. The initial method of disposal was incineration, but this was discontinued as pyres produced carcinogenic dioxins which could be deposited on grass and soil up to 1.6 km from the pyre. Burial was then preferred but, as animals over 5 years of age were considered to present a danger of BSE and there was seepage of fluids into water courses and drinking water, some sites were exhumed. Rendering plants offered insufficient capacity, and disposal at sea met strong objections.

Consequences

Financial

National cost. Estimates of the cost of the outbreak to the UK can not be defined realistically at this stage as many elements are ongoing. They relate not only to direct compensation for slaughtered animals (which exceeded £1 billion as at 20 July) and associated expenditure on disease control (1600 veterinary surgeons, 2000 military personnel, slaughtermen, transport, disinfection procedures, excavation equipment, etc) which also was in excess of £1 billion, but also to the losses incurred by the livestock industry through movement restrictions (e.g. feeding animals with no prospect of sale), and to the losses incurred by other industries (e.g. tourism and small rural businesses).

The estimate by the Institute of Directors of the likely cost to the wider economy of £20 billion, is in agreement with other estimates.

Compensation

. Compensation for slaughtered stock was excessive for some commercial animals. Some owners of commercial stock were able to obtain a valuation which allowed them to leave the industry with a sum substantially in excess of the market value of their stock. In contrast, in many cases compensation was inadequate for pedigree animals. Stock of special genetic importance, including rare breeds, often was undervalued and values were imposed while owners were emotionally vulnerable. Animals culled for welfare reasons received poor compensation; beef animals with a market value of £600 received a maximum of £365. Owners penalised by movement restrictions received no compensation, and the proposed compensation (£10 each) for approximately 1.5 million lightweight lambs likely to be destroyed because of the ban on exports will be circa 35-40% of market value. It seems likely that claims, including compensation for consequential loss and psychological/emotional damage, will be made in the aftermath of the FMD outbreak based on the illegality of the control programme.

Livestock industry

New policies. Livestock are kept on approximately 58% of UK farms, but numbers of animals have been declining in recent years. By 20 July livestock had been slaughtered on 8,811 farms directly as a result of FMD, and from many others as result of the Livestock Welfare Disposal Scheme. In other cases, farmers ceased to trade. Surveys show that many affected farmers will not remain in farming, and many will re-stock at least 30% lower than the previous level. DEFRA officials are formulating a policy of buying up and moth-balling sheep and beef quota to permanently reduce stock numbers. This conforms to projected Government policy where it is envisaged that livestock farming in UK will fall into three categories, of which two are subsidiary to other criteria (e.g. environment, tourism, diversification).

FMD UK/2001 has coincided with a policy to down-grade the livestock industry and remove many small farmers from the land. The UK Government plans a major reduction of circa 25% in the number of farms - mainly small farms - in the aftermath of FMD, with circa 50,000 people leaving the industry. Agriculture in UK will be restructured and focused on large-scale farming industry. This policy is endorsed by the National Farmers Union, but is opposed by those with other interests such as animal welfare, environmental conservation and products which are safe, local and of high quality.

Effect on AnGR. The loss experienced by breeds in each of the three RBI categories of special genetic importance has significantly reduced biodiversity in the native livestock population of UK, with some breeds critically endangered. A detailed census to establish the situation post-FMD is a high priority. The previous census was carried out by the author on behalf of MAFF in 1998 and already work has started on collating current information. There is a recognition of the need to create and develop Gene Banks to act as long-term genetic insurance for the support of living populations, and as a source of genetic material for renewal of breeds critically affected by FMD.

Policy

Inevitably, there must be a review of disease control methods. It is difficult to justify the cost implications of a mass slaughter policy in the context of more frequent outbreaks of FMD. The alternative merits of vaccination and breeding for disease resistance must be evaluated. Breed differences in resistance to FMD have been noted in Hungary, where there was a severe effect in Simmental dairy cattle but insignificant effect in native Grey Steppe cattle.

A wider review of agricultural policy and practices should examine the sustainability of agricultural methods taking into account biological, environmental and financial factors. A report by RBI to the EU (Rare Breeds International, 2001) stated that "attention has been focused too narrowly on maximising production and profit, and that insufficient attention has been paid to food security, animal health and genetic conservation". A critical evaluation of the impact of intensive farming methods, and an assessment of the benefits of extensive systems and local production for local needs are essential elements of the review. Already there is recognition of the need for more effective regulation of long-distance movement of livestock and the feeding of animal products such as swill and meat-and-bone meal.

Conclusions

Systemic failure

FMD/2001 caused massive disruption to normal activities in UK. The scale of the outbreak was a consequence of several factors. There was a complete systemic failure, encompassing many sectors of society, which caused unnecessary loss. Incompetence at Government level was recognised but not eliminated when the Prime Minister declared himself in personal charge of this crisis, and many judged that he failed to make firm decisions on crucial matters or provide adequate leadership.

Inadequacies of Government policy were not effectively exposed by voices of conscience or the media or organisations such as RSPCA. Earlier policy had eroded the network of local abattoirs, and permitted increased activity of livestock dealers. Both these factors resulted in frequent and long-distance movement of livestock which facilitated the spread of the disease. Subsequently, inadequate biosecurity by many parties, including DEFRA employees, compromised the efficiency of control measures.

Disease control policy

Mass slaughter is an archaic and expensive method of disease control which increasingly is unacceptable in the modern world. It has a place in the early stages of an outbreak if it results in rapid control and elimination of the disease, but not as a general policy. The cost of FMD/2001 in UK is untenable.

The argument of protection of partial loss of the £1.2 billion exports of livestock and livestock products, which was used to justify the slaughter policy, is not logical and is not sustainable in comparison with the cost of FMD/2001 estimated in the region of £20 billion.

Alternative methods of control, such as vaccination and breeding for disease resistance, demand urgent and scientific evaluation. The increased risk of further outbreaks strengthens the argument in favour of vaccination. The risk derives primarily from the greater volume of world trade and travel, and maybe from eco-terrorism. The possibility also remains that pockets of FMD carriers persist in the UK sheep and deer populations, and could serve as a source of new infection. The importance of vaccination has been appreciated in the EU where eight foot-and-mouth disease research projects were being conducted by the Research Directorate-General during 2000 and 2001.

Local markets

The expansion of world trade and the influence of WTO increase the danger of spread of disease, and the probability of more frequent outbreaks of FMD in UK.

WTO prevents trade barriers against imports of lower quality and the UK Prime Minister admitted that if the UK did not buy sub-standard meat from overseas, exports would be jeopardised by possible retaliatory international trade sanctions.

In the wake of FMD there is an opportunity to focus more on local production of livestock products with full traceability. The growth of farm shops and farmers' markets shortens the food chain from producer to consumer and should be protected from the inhibiting effect of over-regulation (e.g. HACCP). Native adapted breeds, marketed and processed through local networks of abattoirs and markets, reduce the possibilities for major epidemics and provide a basis for a vigorous local economy.

Genetic diversity

Biodiversity must be protected by maximising the conservation of AnGR ( Animal Genetic Resources) in farm livestock. RBI, as the global NGO (Non Government Organisation) with dedicated interest in this field, has noted that "ongoing erosion of genetic variability within and between domestic breeds of livestock is limiting options to meet challenges in the future" (Rare Breeds International, 2001), and is working actively in co-operation with FAO to minimise further loss. In guidelines for decision-making for the control of FMD, FAO emphasised the importance of genetic conservation as an insurance against change, and recommended a combination of in vivo and in vitro programmes. Control of disease by mass slaughter jeopardises the security of genetic diversity; the use of vaccination is compatible with an ongoing strategy for the in situ conservation of AnGR. RBI has identified breeds with priority for in situ conservation as the core of its policy, and is encouraging the development of Gene Banks to collect and store genetic material from native breeds as a subsidiary element of the support for live populations.

References

Donaldson, A.I., S. Alexanderson, J.H. Sorensen, T. Mikklesen, 2001; Relative risks of the uncontrollable (airborne) spread of FMD by different species. Veterinary Record (May 12), 12 (19), 600-604

Donaldson, A.I., S. Alexandersen, 2001; Relative resistance of pigs to infection by natural aerosols of FMD virus. Veterinary Record (May 12), 12 (19), 600-604

Office International des Epizooties, 2001; OIE/FAO International Scientific Conference on Foot and Mouth Disease. Paris, April 17-18

Rare Breeds International, 2001; Foot-and-Mouth Disease, Recommendations to EU. Rome, April 21

GLH Alderson
20 July 2001

Note to editors:
Paper submitted 20 July 2001
Paper presented at RBI/EAAP/FAO meeting in Budapest on 23 August 2001 Embargo on publication before 24 August 2001