Equine viral arteritis

break of equine viral arteritis (EVA) occurred on a considerable number of Thoroughbred breeding farms in Kentucky in 1984. Subsequent events have shown that this was a watershed event. That occurrence resulted in a dramatic increase in the significance with which this disease would henceforth be perceived by many horse industries worldwide. Greater awareness, surveillance, and improved diagnostic capability collectively have led to an increase in the number of reported outbreaks of EVA over the intervening years. Spread of this infection internationally can almost invariably be attributed to the movement of carrier stallions or shipment of virus-infective semen. The increase in number of confirmed outbreaks of the disease bears little relationship, however, to the known global distribution of the causal agent, equine arteritis virus (EAV). Based on the results of serosurveillance surveys and diagnostic testing, it would appear that the majority of cases of EAV infection continue to be asymptomatic. Where investigated, the virus has not been shown to be a significant cause of abortion or illness and death in young foals. Outbreaks at racetracks, sales yards, etc are very infrequent in occurrence.