Infectious Equine Encephalomyelitis

a viral disease of solidungulate animals (possibly a disease of man as well) characterized by central nervous disorders and physical incapacity. Several varieties are distinguished according to the properties of the virus: Borna disease (recorded in East and West Germany); American infectious equine encephalomyelitis (observed on the American continent); Japanese infectious equine encephalomyelitis (found in Southeast Asia, Japan); infectious equine encephalomyelitis in the USSR.

The clinical manifestations of these diseases are very similar, but their causative agents differ in a number of properties, including the immunological. The disease was eradicated in the USSR in 1960. It has an acute course, with 80 percent of the infected horses dying in the first 24–48 hours. Clinical symptoms are fever, inhibition, uncoordinated movements, jaundice of the mucous membranes, and alternation of depression and excitation. Horses that recover from the disease acquire long-lasting immunity.

Prevention and control call for the destruction of blood-sucking insects and rodents (possible carriers of the causative agent) and quarantine. The viruses that cause American and Japanese infectious equine encephalomyelitis are pathogenic for man. Prevention requires control of mosquitoes, which are transmitters of the virus from diseased animals to man. The persons working with the virus are vaccinated.