Contagious ecthyma is a contagious, viral disease of goats and sheep known by several alternative names, including sore mouth, orf, scabby mouth and contagious pustular dermatitis. Sore mouth is common in goats worldwide and can produce painful, thick scabby sores on the lips and gums. The disease usually runs its course in 1-4 weeks but may be extended when severe secondary infections occur. Complete healing without scarring is the most common outcome. Feed intake may negatively be affected resulting in weight loss.
Sore mouth is not limited to the mouth. A kid with sore mouth lesions can pass the infection to the teats of a doe during suckling. Lesions appearing on udders are painful and the doe may not allow the kids to nurse and/or may develop mastitis. The disease may be passed from infected animals to others. In addition, scabs containing viruses which have contaminated the environment may be another source of infection. Milking equipment and bedding contaminated by infected does are other possible sources of infection. The lesions are crusty, and may be secondarily infected with bacteria such as staphylococci and others. Although the lips and gums are most commonly affected, lesions have been reported on the face, ears, coronary bands, scrotum, teats, vulva, neck, chest and flank.
The sore mouth virus is very hardy and persists for extended periods away from the host in the form of dried scabs from an infected animal. Recovery from the disease gives an immunity for at least one year. Transfer of immunity from the doe to the kid through colostrum has not been conclusively proven. Very young kids that are severely affected may die.
Diagnosis is usually based upon clinical appearance. Laboratory tests may be used for confirmation.
In milder cases, treatment may be of little value. Softening ointments may help. It is important to make sure that affected animals are eating and drinking. Soft, tasty feeds may help to keep intake up. Antibiotics may be indicated if secondary infections are severe. Dairy goats with sores on the udder should be milked last and an antiseptic udder salve may be applied to control bacterial proliferation until self-healing occurs.
Commercial vaccine labeled for both goats and sheep are available on the market and have been of value in some instances. These products should always be used according to product label direction and after consultation with a veterinarian or animal health expert. Vaccinating a clean herd will introduce the disease (the vaccine is a live virus product) to such a herd, and should be done will full consideration of this fact. Scabs appearing at the vaccination site in 1 to 3 days indicate that the vaccine is "taking". Therefore, it is important to vaccinate at least 6 weeks before the show season, so that vaccine scabs will be gone before the first show. Following vaccination, at least two to three weeks are necessary for adequate immunity to take place. Animals are vaccinated in a hairless, protected area. Sites for vaccination include the inside of the ear, the underside of the tail, and others.
It may not be a concern to vaccinate pregnant animals because the vaccine reportedly does not induce abortion. However, the stress of herding pregnant animals into a handling facility and vaccinating them could potentially induce abortion in some animals.
One vaccine manufacturer reports that vaccination of does will not produce immunity in kids. Therefore, vaccination should focus on vaccinating each new kid crop. In some programs, annual revaccination of late pregnant does is performed along with vaccination of the new kid crop.
Disinfection of the pens after all lesions have cleared is recommended in case the owner of in infected herd chooses not to follow a routine vaccination program.
Human Health Concerns
The sore mouth virus may infect man. Persons handling affected animals or vaccinating goats or sheep should wear gloves at all times when handling these animals or the vaccine to protect against acquiring infection.