Orf Virus, a zoonotic disease affecting both animals and humans.
While writing on several animal diseases, I always mention that some of the diseases that affect animals are zoonotic while others are not, this means that, some of these diseases could be transferred to humans while others cannot, on today's topic on animal diseases also, we will be considering the Orf virus which is also known as Sore Mouth Infection. This infection is classified under the member of the parapoxvirus* gene in the Poxvirus family. The virus basically causes infection in goats and sheep and of course, it can be transmitted to humans. Apart from being called sore mouth another name, it is also known as scabby sores, contagious ecthyma, infections with orf disease happen all through the world at least wherever there are small ruminants.
The presence of the orf virus causes skin lesions on the lips, the muzzle, eyelids, nostrils, and ears, on a less common occasion, the udders, genitalia, and feet of the animal get affected. The infection is transmitted to humans through a form of direct contact with the infected animal or through contaminated fomites, in some really rare cases, there could also be human-human transmission. Lesion infection is more visible around the hand, it is more common among ranching communities and for those who process animals for the purpose of consumption. So basically, if you have a sore, a scratch, or a cut and then you touch an infected animal as a human, there is a high possibility of catching the infection, and while sheep and goats can get vaccinated against orf virus, humans can still get infected when they come in close contact with an animal that was vaccinated recently or the one without vaccination. Symptoms of an infected animal are; papules an pustules found on the lips and on the muzzle, it is less commonly found in the mouth of young lambs and on the feet, eyelids, and teats of ewes. The lesion would then progress to a thick crust which may bleed, when a suckling animal has orf, it comes with suckling difficulties which would lead to weight loss. the udder of the mother ewe can also get affected leading to mastitis.
For goats and sheep, the leison could as well be found in the nostrils, the eye region, the coronet, the thigh, the udder, and the axilla. In very rare cases however, when young lambs are involved, the lesion is found on the gum, tongue, roof of the mouth, and esophagus, in some cases as well, leisons can be caused in the rumen. There was once a study that shows an outbreak of the gastrointestinal tract, lungs, heart, buccal cavity, young, lungs, and lips.
In some typical cases, the sheep would become free of the orf virus within one week or two weeks after the disease has successfully run its course, the sheep or farm owner can assist infected lamps with receiving sufficient milk and separating infected stock from the non-infected on to prevent cross-transmission.
Orf virus blister is usually 2-3cm but it has the capability to grow to 5cm, it may also leak fluid before crusting over. Some other symptoms of orf are; High temperature, fatigue, and swollen glands on the inside of your elbow right under your arm.
In humans, there is no specific treatment for the orf virus, the blisters on the skin should go away on their own after about 6 weeks, it should be gently covered to prevent infection, and when it gets infected, recommended antibiotics would provide remedy to the situation. In some cases, however, minor surgery may be required to take out the affected skin area, that is, if the blister does not go off on its own.
Humans can reduce their chances of getting orf virus by following these helpful safety techniques;
Always wash your hands with soap and water immediately after you touch an animal.
Get your sheep and your goats vaccinated against orf.
Constantly clean and disinfect barns and sheds that house the livestock.
Cover any acquired sores or scratches with a waterproof dressing especially when you are handling goats and sheep.
You should see a doctor immediately if you notice any of these symptoms;
You have a painful mark or blister, that is red and swollen, then accompanied by a high temperature.
You have several blisters that are big and painful or that blister that regularly disappears and re-appears.
You have a particular blister or a particular mark on your finger, your hand, your arm or your face that has consistently increased in size or that has refused to heal after a long period of six weeks.
You have a rash that has the appearance of a bulls-eye like with a dark center, then it is surrounded by a paler ring and a darker ring forming around the outer region.
Although orf virus infection may not sound like a big deal when the case is minimal, it could come with complications, the severity of the virus affects more people than others, so there is a stronger chance of having a complicated case of the infection if; you have a weak immune system or you have existing conditions like HIV or previous treatment of chemotherapy. Possible complications of the infection are;
- Bacterial infection.
- Bullous pemphigoid skin condition that causes large blisters.
- Erythema multiforme.
A vet should as well be contacted immediately if there is a displayed symptom because this symptom could be a misdiagnose of a more serious disease deserving a more content/urgent treatment.
Conclusion.
Orf virus is a zoonotic disease which means it is an infection type that can affect animals and spread to humans, it could naturally go away on its own after the infection has taken its course, or it could cause severe complications to the affected animals. It is best to always visit a veterinary doctor once there is a noticed sign of the virus as it could even be the emergence of a more severe infection. Humans on the other hand, that are exposed to sheep and goats need to protect themselves from getting infected.