There are 7 serotypes. Outbreak control depends on rapid diagnosis and rigid restriction of nonessential movement both into and out of affected farms and the surrounding countryside. The last outbreak in Canada occurred in 1952. The virus can be spread both directly and indirectly. It is readily airborne and is also spread by the movement of animals, people and vehicles.
Blisters develop a few days after infection.
Malaise, lameness and secondary bacterial infections soon follow. The most serious effects are seen in dairy cattle, with the resulting economic disaster from declining milk yields, abortion and sterility. Rarely, the infection crosses to humans and produces a mild viremia, with blistering. The last reported human case in Great Britain occurred in 1966. An animal vaccine is available, but because current serologic tests cannot distinguish between infected and vaccinated animals, FMD-free countries will not import vaccinated animals.