Orf is a contagious viral skin disease in goats (and sheep) that causes painful, crusty sores around the mouth, lips, and nostrils. It’s caused by a parapoxvirus and is also known as “sore mouth” or contagious ecthyma. The infection typically runs its course in about six weeks, but it can cause serious problems for nursing kids and does, and it can spread to humans through direct contact.
How Goats Get Orf
The virus needs broken skin to establish infection. A cut, scrape, or abrasion is the entry point. This is why outbreaks often follow exposure to rough browse, thistles, coarse hay, or dry stubble that scratches the delicate skin around the mouth. Feeders with sharp edges, fighting between bucks, and any situation that causes small wounds around the face can set the stage.
Once the virus is on a property, it’s difficult to eliminate. The dried scabs that fall from infected animals contain live virus that can persist in the environment for months to years, contaminating pastures, feeders, fencing, and bedding. New animals introduced to the herd can bring the virus with them, which is one reason USDA biosecurity guidelines recommend quarantining any new goats for a minimum of 30 days before mixing them with your existing herd.
What the Lesions Look Like
After about a week of incubation, the first visible signs appear as small red bumps, usually on the lips, gums, nostrils, or corners of the mouth. From there, the disease moves through six roughly week-long stages:
- Week 1: Small red raised bumps appear at the infection site.
- Week 2: The bumps develop into ring-shaped nodules with a red border and a darker, dying center, sometimes described as a “target” pattern.
- Week 3: The nodules become wet and begin to weep fluid. This is the acute, most contagious stage.
- Week 4: The sores begin to dry out.
- Week 5: A thick, dry crust forms over the nodules, giving them the classic “scabby mouth” appearance.
- Week 6: The scabs shrink and fall off as the skin heals underneath.
Lesions can also appear on the udder and teats of does, on the lower legs, and occasionally around the genitals. In mild cases you might see just a few small scabs at the lip margins. Severe cases can produce large, proliferative masses that make it painful or impossible for the goat to eat.
Why Orf Is Dangerous for Kids and Does
The biggest practical concern with orf is what it does to nursing. Kids with painful mouth sores often refuse to nurse or nurse less aggressively, which leads to poor weight gain, dehydration, and vulnerability to other infections. In very young kids, this can be fatal if they aren’t supplemented with bottle feeding.
The problem goes both directions. Kids with mouth lesions can transfer the virus to the doe’s teats and udder during nursing. Once a doe’s teats are infected and painful, she may refuse to let kids nurse at all, sometimes lifting a rear foot as if lame to push them away. The combination of damaged teat skin and milk that isn’t being drawn out creates ideal conditions for mastitis, a bacterial udder infection. Mastitis leads to treatment costs, premature culling, and reduced performance of the kids who depend on that doe’s milk.
Treatment and Supportive Care
There is no antiviral treatment that kills the orf virus. The infection has to run its course, so management focuses on keeping the animal comfortable, preventing secondary bacterial infections, and ensuring adequate nutrition.
For kids that are struggling to eat, softening feed and offering warm water can help. Kids that stop nursing entirely may need to be bottle-fed until their mouth heals enough to latch on again. Keeping lesions clean and dry reduces the chance of bacteria colonizing the damaged skin. If sores become swollen, foul-smelling, or start producing pus, a secondary bacterial infection has likely set in, and your veterinarian can prescribe appropriate treatment.
Isolating visibly infected animals from the rest of the herd helps slow the spread, though by the time you notice the first case, other goats have likely already been exposed. Clean and disinfect any shared equipment, feeders, and water troughs. Remove the dried scabs from bedding areas when possible, since each fallen scab is a packet of virus waiting for the next animal.
Vaccination
A live virus vaccine is available for orf. It’s applied by dipping a forked needle into the vaccine and scratching the bare skin on the inside of the goat’s thigh. You then watch for a local reaction at the scratch site over the following days to confirm the vaccine “took.” The vaccine doesn’t prevent infection entirely, but it reduces the severity of lesions significantly.
There’s an important catch: the vaccine contains live virus. Using it on a property that has never had orf will introduce the virus to your farm permanently. For this reason, vaccination is generally reserved for herds that already have a history of outbreaks or that are at high risk due to show circuits or frequent animal introductions.
Vaccinate at least six to eight weeks before the expected risk period, such as before kidding season, so the immune response has time to develop. Does can be vaccinated before kidding so that kids receive some passive immunity through colostrum.
Orf Can Spread to Humans
Orf is zoonotic, meaning it can pass from goats to people. Humans typically pick it up through direct contact with infected animals or contaminated equipment. The virus enters through a break in the skin, so even a small hangnail or paper cut is enough.
In humans, orf produces a single nodule (occasionally a few) at the site of contact, usually on the hands or fingers. The lesion follows the same six-stage progression seen in goats, each stage lasting roughly a week, for a total healing time of about six weeks. The sore can be alarming to look at, sometimes growing to an inch or more across, but it almost always resolves on its own without scarring.
People can also become infected from accidental contact with the live vaccine. If you’re vaccinating your herd, cover any cuts or scratches on your hands beforehand and wear gloves. If you accidentally scratch yourself with the vaccine applicator, wash the site with disinfectant immediately. The same precautions apply when handling scabby animals: wear gloves, wash your hands thoroughly afterward, and avoid touching your face during the process.
Preventing Outbreaks
Quarantine is your first line of defense. Keep new goats isolated for at least 30 days and watch for any developing lesions before introducing them to the herd. Limit contact with outside animals at shows, fairs, and breeding events, and inspect returning animals carefully.
Reduce the chance of mouth injuries by managing your pastures for thorny or abrasive plants, keeping feeders in good repair, and providing feed that doesn’t require aggressive chewing against rough surfaces. Disinfect shared equipment regularly, limit visitor access to your goat areas, and use individual needles (or disinfect between animals) when giving injections. During kidding season, keep kidding areas clean and remove birthing material promptly to minimize environmental contamination.
Goats that recover from orf develop immunity, but it isn’t lifelong. Reinfection can occur, though repeat cases tend to be milder. In herds where orf is established, most animals will encounter the virus at some point, and the goal shifts from total prevention to minimizing the severity and protecting the most vulnerable animals: newborn kids and does close to kidding.