sore mouth
- Also called:
- scabby mouth, orf, contagious pustular dermatitis, or contagious ecthyma (CE)
sore mouth, viral disease of sheep and goats. The disease is characterized by the emergence of blisters, pustules, ulcers, and scabs on the lips especially but also on the face, the ears, and sometimes the legs. In severe cases, sores form inside the mouth. Sores may also appear on the teats of ewes or does that nurse infected young, which may result in the mother abandoning her young.
Sore mouth is caused by infection with orf virus, a type of parapoxvirus in the poxvirus family (Poxviridae). The virus can be transmitted via direct muzzle-to-muzzle contact between animals, via open cuts or abrasions, or through nursing of infected offspring. The virus is hardy and can survive for long periods of time in bedding, pastures, and buildings, making it difficult to eliminate.
Infections occur in the spring and summer and heal in about a month. Repeat infections are common in flocks and on farms where the virus persists. Disinfection of buildings and feeding troughs, removal of thick brush from pastures, and washing hands after touching infected animals can help reduce the risk of transmission. Vaccination can further protect against infection; because vaccination can cause sore mouth, it generally is used only to prevent reinfection in flocks that have been previously exposed.
Humans who work around infected animals sometimes become infected themselves. Symptoms in humans typically include the development of ulcerative sores and nodules on the hands.