Orf is an infectious disease of sheep and goats affecting primarily the lips of young animals. The disease also goes by the names "Contagious Ecthyma, Contagious pustular dermatitis, and Sore-Mouth" and is caused by a pox virus The virus may occasionally infect humans. The virus is highly resistant to drying and may remain infectious in dried scabs for up to 12 years. Humans become infected with the virus by direct contact with infected sheep or equipment contaminated with body fluids. The disease in humans is usually characterized by a single papular or pustular lesion (small bump/swelling) where the virus enters the skin (e.g. on the hand). The papule usually becomes painful and gradually becomes a firm weeping nodule. Regional lymph nodes may also become swollen. Usually the course of the disease lasts 2-4 weeks following a 3-7 day incubation. More widespread disease may occur, as well as severe ocular lesions.

Prevention

• All persons working with infected sheep (the cage or room will be marked) should protect their hands by wearing gloves and washing hands as soon as possible after exposure.
• All equipment used on sheep should be washed and decontaminated. It should be remembered that gates and pens also may harbor the virus - gloves should be worn at all times working in the animal rooms.