By the Centers for Disease Control & Prevention
INFECTION IN ANIMALS
Sore mouth is principally found in sheep and goats. In the United States, 40% of sheep operations reported sore mouth infections within their flock during 1998-2000, this according to a 2001 survey performed by USDA.
Signs of an orf virus infection
Sores are typically found on the lips, muzzle, and in the mouth
Earl in the infection, sores appear as blisters that develop into crusty scabs
Sheep and goats may get sores on their lower legs and teats, especially when ewes or does are nursing infected lambs or kids. Young animals may have difficulty nursing and may require bottle or tub feeding. Nursing ewes or does with lesions on their udders may abandon their lambs or kids, and older animals with oral lesions may also require nutritional support.
Except in rare cases, animals recover completely from sore mouth infections within a month. Particular breed, especially Boer goats, may be especially susceptible and may have severe infection.
Animals can become infected more than once in their lifetime but repeat infections usually occur after a year’s time and are generally less severe.
What other diseases can look like sore mouth?
Foot-and mouth disease (FMD) is a highly contagious and sometimes fatal viral disease that can affect sheep, goats, cattle, swine, and other cloven-hoofed animals. FMD can be confused with similar but less harmful diseases, including sore mouth. FMD has not occurred in the United States since 1929. If your animal (s) exhibit more severe symptoms than lesions in the oral cavity, teats, and lower legs such as excessive salivation or lameness immediately report it to your veterinarian, to stat or federal animal disease control officials, or to your county agricultural agent.
How do animals become infected?
Material from the lesions of an infected animal contains the virus. The virus can be transmitted to other animals through cuts or abrasions in the skin. The teats of ewes or does may become infected through nursing lambs or kids. Any direct contact between animals—muzzle to muzzle or skin to skin—can result in transmission of the virus between animals.
Orf virus is particularly hardy in scab material and can remain viable in the environment for months, possibly years. Pastures, bedding, feed and feed troughs, and buildings may become contaminated with orf virus from released scab or lesion material making it difficult to completely eliminate orf virus from the immediate environment once an infected animal is present.
Is there a vaccine available?
There are commercially available preparations of live virus marketed as vaccines. Producers considering using an orf vaccine product in their flock should consult a veterinarian. Vaccinations practices vary depending on breed and geographic location. Because the orf vaccine is a live virus preparation, its use is only suggested for flocks that have previously experienced orf virus infection or in which vaccine has previously been used.
INFECTION IN PEOPLE
Infection with orf virus is usually confined to the epidermis (top layer) of the skin. Lesions (one to a few) or nodules will often occur on the fingers, hands, or the forearms. Lesions begin as small papules that will become ulcerative in nature. Orf virus lesions typically progress through six stages each lasting approximately one week. Other symptoms may include a mild fever, malaise (fatigue), or local swelling of lymph nodes. Lesions generally range in size from 2-3 cm but can be as large as 5 cm. they can be painful but usually resolve on their own without scarring.
How do people become infected with orf virus?
Orf virus infections in humans typically occur when broken skin comes into contact with the virus from infected animals or contaminated equipment. Activities that may put you at rick for infection include:
¨ Bottle feeding, tube feeding or shearing sheep or goats.
¨ Petting or having casual contact with infectd animals
¨ Handling infected equipment such as a harness
¨ Being bitten by an infected animal.
Orf virus is not transmitted from one infected person to another. Orf virus infections do not generate enduring immunity, a person can be infected multiple times throughout his or her life, but subsequent infections ma be less pronounced and may heal more quickly.
What should I do if I think I’ve become infected?
Currently there is no approved treatment for an orf virus infection. However, the lesion can become infected with bacteria if not properly managed.
The lesion should be kept dry and covered to prevent a secondary infection with bacteria. While working with animals or during manual labor in which the lesions might get wet, use a watertight bandage. To promote healing, a non-weeping sore can be uncovered at bedtime or covered loosely if still weeping.
If you are experiencing pain, fever, or notice that the lesion is becoming rapidly larger or spreading, you should see your doctor.
A number of infectious agents can be transmitted from sheep and goats to humans. Some may even resemble orf in appearance but may be more serious. One such agent is anthrax, which can cause lethal disease in both goats and humans. You should seek medical attention if you notice a lesion that you cannot explain or the lesion is becoming rapidly larger.
Are people with a compromised immune system at greater risk from an orf virus infection?
Persons whose immune systems are compromised or suppressed due to infection with HIV, lupus, or cancer therapy, etc., can develop serious symptoms following orf virus infection, including large tumor-like lesions, progressive disease development of multiple lesions, or erythema multiforme reactions involving rashes on the mucous membranes and skin.
How can I keep from getting an orf virus infection?
People can become infected with orf virus by having direct contact with infected animals or through equipment contaminated with the virus. Some animals may or may not have visible lesions (sores) but may still be able to spread the virus.
Wear non-porous rubber or latex gloves when handling sheep or goats, especially when you have an open cut or sore and are handling the animals mouth/muzzle area.
Proactive good hand hygiene by washing with clean, warm water and soap for at least 20 seconds, by using a waterless alcohol-based hand rub when soap is not available, and hands are not visibly soiled.