foot-and-mouth disease

foot-and-mouth disease highly contagious disease almost exclusive to cattle, sheep, swine, goats, and other cloven-hoofed animals. It is caused by a virus that was identified in 1897. Among its symptoms are fever, loss of appetite and weight, and blisters on the mucous membranes, especially those of the mouth, feet, and udder. Discharge from the blisters is heavily infected with the virus, as are saliva, milk, urine, and other secretions. Thus the disease is readily spread by contact; by contaminated food, water, soil, or other materials; or through the air. Humans, who seldom contract the disease, may be carriers, as may rats, dogs, birds, wild animals, and frozen meats.

Quarantine, slaughter and complete disposal of infected animals, and disinfection of contaminated material, are prescribed to limit contagion. There is no effective treatment. With vaccines, introduced in 1938, and sanitary controls, foot-and-mouth disease has been excluded or eliminated from North and Central America, Australia and New Zealand, Japan, and Ireland; and occurrences have become infrequent in Great Britain and continental Europe. The disease persists through much of Asia, Africa, and South America.

Bibliography: See publications of the U.S. Dept. of Agriculture.

foot-and-mouth dis·ease • n. a contagious viral disease of cattle and sheep, causing ulceration of the hoofs and around the mouth.

foot-and-mouth disease (FMD) (hoof-and-mouth disease) Highly infectious viral disease affecting practically all cloven-hoofed mammals, including cattle, sheep, pigs (not carriers), and goats. The disease does not affect humans or horses. It is characterized by fever, followed by the eruption of blisters mainly in the mouth and around the hoofs. Lameness is the most noticeable sign. The average incubation period is 3–8 days. Foot-and-mouth is often fatal for young animals and reduces the yield from milk-producing animals. The virus is largely present in the discharge from blisters, but also occurs in the saliva, milk and dung of infected animals. Wind may also spread the virus over large distances. The mortality rate in mild epizootics is c.5%, but malignant foot-and mouth has caused losses of up to 50%. The traditional method of controlling the disease has been to rigorously quarantine areas of outbreak, and quickly slaughter and dispose of all infected or susceptible animals. An alternative or complementary method is vaccination. This method is costly and not effective against all seven strains of foot-and-mouth. A 1967 outbreak in the UK led to the slaughter of more than 430,000 animals. Another outbreak in 2001 resulted in the killing of more than 3 million animals. In the USA, the last major outbreak was in 1929.