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Foot-and-mouth disease (FMD) is one of the biggest threats to animal health in European countries. In the last 22?years (1985-2006), FMD has occurred 37 times in 14 European countries.Serotype O was most frequently involved in these outbreaks followed by A, C and Asia 1. Sometimes, epidemics were very limited and at other times, they were the cause of devastating economic losses. In most cases (2237), the origin of the outbreaks could not be determined. For some of these outbreaks, however, routes of introduction and spread were identified through epidemiological inquiries. Moreover, in some cases, the origin of the virus was also traced by phylogenetic analysis of the partial or complete sequences of VP1 genes. Lessons learned from the outbreaks are still useful as most of the same risk factors persist. However, efforts made by FMD-free countries to help those where the disease is endemic are a valuable strategy for the reduction of the global risk. The present and the future potential sources of FMD infection need to be identified to best focus European efforts.

Risk assessment procedures frequently require quantitative data on the prevalence of the disease in question. Although most countries are members of the World Organization for Animal Health (OIE), the importance attached to foot-and-mouth disease (FMD) reporting or surveillance for infection varies enormously between infected countries. There is a general consensus that FMD outbreaks in endemic countries are greatly under-reported, to a degree related either to the economic or the political development level of the country. This exploratory study was first undertaken by FAO, but thereafter extended and reviewed by the working group on FMD risk co-ordinated by the European Food Safety Authority (EFSA). The paper attempts to overcome the lack of reporting through using expert opinion to extrapolate incidence indices from countries considered to have 'representative' levels of FMD. These were combined with livestock density distributions to provide maps of prevalence indices, which were found to be highest in China (pigs), India (cattle), the Near East (small ruminants) and the Sahel (small ruminants and cattle). Similar patterns were found when weighted expert rankings of a range of additional ranked disease parameters were also produced, and then combined with susceptible animal densities to produce a weighted multi-species density. Results suggest that the methods can provide useful information at both national and sub-national resolution, even for countries for which quantitative FMD data is currently unavailable: two of the regions identified provide little or no data on a regular basis to the OIE and therefore may be overlooked if the level of officially reported FMD is only used. As the estimated prevalences are based on recent disease history and expert opinion, they are most likely to be inaccurate where FMD incursions are infrequent as a result of the preventive measures and geographical and trade isolation. This study, therefore, highlights the need for specific detailed country risk assessments where livestock trade is under consideration. Validating the approach including ground truthing, will require collaboration between a number of agencies and institutions, in critical countries, particularly those with high disease burdens that share borders or trade livestock with currently FMD-free nations.

In the wake of on-going successful programmes for global eradication of rinderpest and the current effort to contain the spread of avian influenza, the progressive world-wide control of FMD must be regarded as a major contribution to the international public good. FMD is the single most animal disease constraint to international trade in animal products. Its control is relevant, on the one hand, to protecting the livestock industries of industrialised countries and, on the other, to the livelihoods and income generation of developing countries, where, as a general rule, FMD continues to be endemic.

Foot-and-Mouth Disease (FMD) is a clinical syndrome in animals due to FMD virus that exists in seven serotypes, whereby recovery from one sero-type does not confer immunity against the other six. So when considering intervention strategies in endemic settings, it is important to take account of the characteristics of the different serotypes in different ecological systems. FMD serotypes are not uniformly distributed in the regions of the world where the disease still occurs. For example, the cumulative incidence of FMD serotypes show that six of the seven serotypes of FMD (O, A, C, SAT-1, SAT-2, SAT-3) have occurred in Africa, while Asia contends with four sero-types (O, A, C, Asia-1), and South America with only three (O, A, C). Periodically there have been incursions of Types SAT-1 and SAT-2 from Africa into the Middle East.

Summary Three strains of foot-and-mouth disease virus were shown to contain significant amounts of naturally occurring 75 S, empty particles as well as the infectious, 140 S full particles. One of these strains — A Pando (1970) — was studied in detail.

Summary Some of the factors which affect the buoyant density in caesium chloride of foot-and-mouth disease virus were investigated. Under standard conditions, the buoyant densities of a range of vaccine virus strains, representing all seven serotypes, were found to be unrelated to their potential of being formulated into effective vaccines. In some virus strains, a small amount of naturally occurring high and/or low density components were observed and these components were examined in more detail in one virus strain.

Summary Experiments are described for the evaluation of the single radial haemolysis (SRH) technique applied to FMD virus, using a method involving the coupling of either antigen or antibody to sheep erythrocytes.

Summary An investigation of persistent cell deaths of BHK 21 suspension cells during subculturing resulted in the isolation of a viral agent. The agent was isolated from samples of dead cells, cell growth media and 2 batches of calf serum. It was established that the agent was associated with the use of certain batches of calf serum. The isolated virus was found to replicate effectively only in rapidly growing BHK cell cultures. In monolayers it caused the formation of large intranuclear inclusion bodies. The isolate was a strong haemagglutinin; it was stable to ether, chloroform, pH 3 and heating at 56° C. It was shown to be a DNA-virus and by electron-microscopy it was evident as unenveloped spherical, small particles (21 nm in diameter). In sucrose density gradients the virus sedimented as 2 peaks at approximately 114S and 85-92S, and by caesium chloride equilibrium centrifugation, two main peaks at densities of 1.39 and 1.31 g/ml were evident with a minor peak at 1.35. The capsid of the complete virion consisted of 3 polypeptides. The agent has therefore been provisionally designated a member of the Parvoviridae family, genus parvovirus. Serologically it was found to be related to MVM. The isolated parvovirus was inactivated by 0.05 per cent peracetic acid and 0.05 per cent acetylethyleneimine.

Infectious bovine rhinotracheitis (IBR) virus was identified for the first time in Tanzania. The virus isolations were made from cattle affected with respiratory diseases. Concurrent infection with foot-and-mouth disease was observed and enhanced the severity of the illness.

INFECTIOUS bovine rhinotracheitis (IBR), first described in the United States as a respiratory disease of feedlot cattle1,2, has been identified in many countries including Tchad3and South Africa4. Serological evidence suggests that the virus is widespread in the Cameroons, the Central African Republic5and Nigeria6. There are, however, no published reports of the disease in East Africa.