The most prominent news item in this issue is certainly the further spread of foot and mouth disease (FMD) in the United Kingdom, with foci in France. The Pirbright FMD laboratory reports that the UK virus is a Type O Strain PanAsia - Topotype ME-SA. Other countries in which this strain was isolated during the year 2000 are: Cambodia, Iran, Japan, Malaysia, Mongolia, Nepal (probably), Russia, South Africa, South Korea, Taiwan, Thailand, Turkey and the United Arab Emirates. Details of FMDV strain identification 2000-2001 have been compiled by Nick Knowles of The Institute of Animal Health. The Institute of Animal Health also has a web page dedicated to FMD, which provides extensive information on the disease and its causative virus and it is updated regularly. The cost of the epidemic in Great Britain is now estimated at £9 billion, with a further £3 billion in lost tax revenue.

For VETERINARY SCIENCES TOMORROW, the issue of the EU non-vaccination policy is the most important bone of contention. There is an increasing loss of overseas confidence in the control measures implemented by Britian’s MAFF (Ministry of Agriculture Food and Fisheries). The German Organisation of State Veterinarians (Bundesverband der beamteten Tierärzte) expressed the opinion that full vaccination of animals in Britain is needed to control the situation. Millions of doses of vaccine could be made available quickly, which would provide protection after 4-6 days. The German National Farmers’ Organisation (Deutsche Bauernverband) is urging politicians to re-evaluate the non-vaccination policy.

The main problem with conventional FMD vaccines is that they contain the full complement of the FMDV proteins, and the antibodies induced by them are identical to those in animals after infection, which may harbour the virus. However, workers at the Plum Island FMDV Laboratory, the US Department of Agriculture's secure research facility, are in the process of developing a marker vaccine. They have inserted DNA copies of capsid protein genes of FMDV into the genome of a human adenovirus. After vaccination, infected cells produce FMD viral capsid protein and trigger an immune response. The adenovirus infection is abortive in cattle, and the vaccine confers protection after seven days. Because the adenovirus does not contain the genes of all FMD viral proteins, vaccinated and infected animals could be distinguish by testing for antibodies to the missing viral proteins. This principle has been found to work well in a pseudorabies (Aujeszky’s disease) marker vaccine.

Marker vaccines could be used to ring-vaccinate animals in the event of an outbreak and, if accompanied by proper management measures, to contain the focus. If vaccinated animals are tested regularly to ensure they have not been exposed to wild-type virus the country could be declared disease-free, as long as these tests are negative. Researchers at the Institute for Animal Science and Health in Lelystad, The Netherlands, have developed similarly traceable vaccines, though by following a different strategy. Their preparations are based on isolated virion capsid proteins, which induce homologous antibodies, some of which are protective, after injection. The marker character is due to the fact that no immune reaction occurs against the viral RNA polymerase (expressed during replication). Antibodies directed against this protein would therefore indicate an infection by field virus. The vaccine has been exported to several countries including Vietnam, Taiwan and Saudi Arabia.

Other foci of FMD can be expected, and indeed have been identified. Only within the last week ProMed-mail has reported in its news section (Today on ProMed-mail) that outbreaks have been confirmed in Palestine (13 cases in the West Bank; 16 March) and in Saudi Arabia (10 cases in Riyadh, Madinah and the Eastern Province; 20 March).