Contagious Ecthyma - Commonly known as Orf
What is Contagious Ecthyma?
Contagious Ecthyma is a highly contagious skin disease commonly seen in goats and sheep. The disease is found worldwide and is caused by a parapoxovirus. The disease is often more severe in goats than in sheep, and kids and lambs are more susceptible to the disease than adults. Contagious Ecthyma is known by several other names including orf, scabby mouth and sore mouth.
What are the symptoms in goats?
Blister-like lesions typically develop on the mouth and muzzle approximately 4-8 days after the animal is exposed to the virus. These blisters then become crusty scabs. Lesions can also be seen on other parts of the body including face, ears, teats, feet (coronary band), vulva and scrotum. Severe, painful lesions in and around the mouth of kids may prevent them from nursing or eating. Does with sores on their teats (particularly teat ends) may refuse to let their kid(s) nurse. This may lead to kid starvation. Most adult goats with lesions around the mouth will continue to eat and milk well. However, secondary bacterial infections may invade teat lesions resulting in mastitis in the doe. Lesions on the feet may cause lameness. Uncomplicated lesions typically heal within one month. Animals with weakened immune systems may show more severe signs of disease. It is common to see 100 percent of kids in a herd infected; however deaths from this disease are rare.
How does it spread?
The disease is spread via direct contact with an infected animal or indirectly from a contaminated environment (equipment, feed troughs, bedding). The virus enters the body through broken or damaged skin (e.g. coarse feeds that cause abrasions to the inside of the mouth). Nursing kids may spread the infection to the udders of susceptible does. The virus remains viable on the skin for approximately one month after the lesions have healed. Not only are scabs that fall to the ground a source of infection, but carrier animals, those that appear healthy but shed the virus, can also spread the disease (particularly during times of stress). The virus is very hardy, which makes it difficult to control. It can survive for months to years in cool, dry environments; but is destroyed by high and very low temperatures.
Do animals develop immunity?
Once infected, immunity to the disease is not life-long. Immunity is reported to last approximately 2-3 years. Reinfection after this time is possible, although the disease is less severe.
How is it treated?
Treatment of individually infected animals is not necessary unless lesions are severe. Severely affected kids will require good nursing care to ensure that they are eating and drinking. Does and ewes may require antibiotic treatment if they develop mastitis. Udder salves may be used to soften scabs on teats.
It is important to keep affected areas clean and dry to prevent secondary bacterial infections and maggot infestation. Do not pick off scabs. There are a number of products that have been reported to speed healing. However, most have not changed the course of healing compared to no treatment, nor do they consider milk and meat withdrawal times. Consult your veterinarian for more information on this disease or to discuss treatment options.
How is it prevented?
New animals entering the herd should be quarantined (3-4 weeks) before mixing with other animals on the farm. Remember, "Buyer Beware" if you are considering purchasing animals. Isolating infected animals may help to prevent the spread of the disease. Cleaning and disinfecting pens may also help reduce the contamination in the environment. Unfortunately, once the virus has entered a herd, it is difficult to eradicate. There are no commercial vaccines available in Canada. The Contagious Ecthyma vaccine available in the USA is a live vaccine and is only used in chronically infected herds. Use of the live vaccine in disease-free herds is not recommended since it will bring the virus into those herds.
Can it be spread to humans?
Yes, goats and sheep can spread the disease to humans - Contagious Ecthyma is a zoonotic disease. If exposed, humans can develop the lesion(s) in 3-7days. A single, red sore is typically seen on a finger, hand or other exposed part of the body. The lesion may be painful but it tends to heal spontaneously without scarring, in 3-6 weeks. People do not infect other people. If you experience more severe pain, fever, or notice that the sore is becoming infected, getting larger or spreading, you should see your doctor. Any person handling an affected animal should wear gloves. Hands should be washed with soap and water frequently.
For more information:
Toll Free: 1-877-424-1300