What Is Orf Virus?
Orf (also known as contagious ecthyma) is a contagious skin disease caused by a parapoxvirus. It affects sheep and goats, but all ruminant species are susceptible. It can also be transmitted to humans (especially children who drink raw goat milk) resulting in a self-limiting painful cutaneous infection. The skin lesions can sometimes be confused with those caused by foot-and-mouth disease (FMD) but Orf lesions are usually seen on the teats and/or lips whereas the lesions of FMD are usually found between the hooves and on the muzzle. Lesions are not usually seen in the mouth or on the feet in Orf.
The virus can survive for long periods of time in sheepfolds, yards and on infected equipment. This, combined with the fact that the disease is spread by direct contact and also via contaminated equipment, fomites and dogs means that it is challenging to control.
How Does It Spread?
Orf virus spreads via direct contact between animals. Transmission of infection requires live virus to get into a skin break. Contaminated equipment, such as ear tags, and dogs that come in contact with infected flocks can also spread the virus.
A person can get orf from direct contact with an infected sheep or goat, especially with open lesions. If the person gets infected, they may remain infectious to other people for up to two weeks. Although they may not have obvious symptoms, they may be able to spread the virus, especially to young children.
In young children, orf commonly leads to a form of mouth infection known as orf stomatitis. This occurs during the late winter and spring months when children are more likely to be drinking raw goat’s milk. Orf stomatitis can mimic hand, foot, and mouth disease (HFMD) because they both cause skin lesions on the mouth and hands and feet due to a viral infection.
Preventing Orf Virus Infection
Orf virus is usually not seen in animals that are kept in barns and stalls; it primarily affects sheep and goats that spend a lot of time grazing outdoors. Because the virus can survive for a long time in the environment, it’s important to remove all hay, uneaten feed, straw, manure and other waste materials when animals are indoors. These items attract birds, which can carry mites into the barn. Mites can carry the orf virus.
If animals with orf lesions are brought to the farm, they should be kept separate from the main flock.
When working with infected animals or working with equipment that may be contaminated, disposable gloves and protective footwear should be worn.
In people, orf virus can be prevented by:
* Avoiding contact with infected animals
* Avoiding drinking raw goat’s milk
* Washing hands with warm soap and water after being around farm animals
* Not touching your mouth or eyes with dirty hands
If you think you or someone you know has orf virus, it’s important to see a doctor or other healthcare provider.