Orf, Contagious Ecthyma, Sore Mouth




This disease affects sheep and goats and is caused by a highly contagious virus. Lesions most commonly occur on the mouth and face but can also occur on the feet, teats and genitalia. The virus is present worldwide and can remain infective in scabs in the environment for months to years.

The virus is spread by direct contact between animals or indirect contact with environmental contaminants. It enters through abrasions or wounds of the mouth, teat, feet or genitalia. It then localizes in the tissues and is shed in scabs that fall off from lesions as they dry. Animals that are kept in the same area are at the greatest risk.

The infection is self-limiting, with most animals developing protective immunity; however reinfection is possible. This disease usually affects kids.

Signs: Early signs are small bumps or blisters on affected skin, usually around the mouth. Thick brown to black crusts form and are most evident. Lesions typically resolve in 14 to 21 days. Nursing lambs or kids are most likely to spread the disease to udders of susceptible ewes or does. Oral lesions may become severe enough to cause affected animals to stop eating. Does can develop secondary mastitis; kids may starve if their mouths are too painful to nurse or their does don’t let kids nurse on painful teats.

Diagnosis: Observation of clinical signs and lesion biopsy if necessary.

Treatment: There is no specific treatment. Supportive care of severly affected individual animals (e.g. fluids) may be necessary.

Prevention: Affected animals should be separated from all other animals. Monitor exposed animals carefully. Prevent scabs from falling off into the environment if possible. Vaccines are available but not recommended unless the disease is already present in a herd. All kids should be vaccinated when young on farms where soremouth has been a problem. Disinfect all contaminated equipment and facilities after thorough saop-and-water cleaning. Animals going to and from shows and sales are at high risk.

Contagious ecthyma is highly zoonotic and may produce lesions on the hands or fingers of a person handling infected animals. Therefore, it is extremely important to practice good hygiene. Disposable gloves should be worn when handling these animals and then properly disposed off in a trash can. Hands should be cleaned with an antimicrobial cleanser after handling.