Does your dog have warts? Warts in dogs are relatively common. They may look unappealing and cause worry to dog owners. Fortunately, there are ways to treat warts in dogs and ways to prevent your dog from getting warts in the first place.
What Are Warts?
Warts in dogs are technically called viral papillomas. These non-cancerous skin growths originate from strains of canine papillomavirus. Warts often appear on a dog's muzzle and in the mouth. They may also occur on the face, abdomen, and between the toes.
Dogs may develop skin bumps mistaken for warts. These usually are other types of skin growths, such as sebaceous gland tumors, moles, or skin tags. These skin growths may be benign or malignant. All types of skin growths should be examined by a veterinarian so they can be properly diagnosed and treated.
Signs of Warts on Dogs
Warts in dogs may be round, oval, or irregularly shaped with a cauliflower-like texture. They are typically pea-sized or larger and pink to gray in color. Canine papillomas and may occur alone but are more commonly seen in clusters.
Canine papillomas are usually seen on dogs' muzzles and inside their mouths. They often grow on the gums, lips, soft palate, and throat, but are also seen around the eyes, on the abdomen, between the toes, and on the footpads.
Warts may become inflamed, infected, and painful when found in areas prone to friction or chewing. In severe cases, they may get in the way of eating and swallowing. Veterinary treatment is necessary if warts have an impact on your dog's quality of life.
Causes of Warts
There are several strains of canine papillomavirus that can be transmitted between dogs and lead to the development of warts. Dogs usually pass these viruses to one another via direct contact. The virus may live in the environment, so dogs may be able to pass the virus through toys, bedding, and other surfaces.
Warts in and around the mouth are by far the most common types seen in dogs. These are called oral papillomas and are caused by canine papilloma virus-1 or CVP-1. Warts from CVP-1 may also develop on the eyelids or between the toes, but these are less common. CVP-1 typically occurs in young dogs (up to two years old) due to their immature immune systems.
Dogs with CVP-2 are most likely to develop warts on the abdomen, footpads, or in between the toes. Warts caused by CVP-2 may be seen in dogs of all ages.
Papillomavirus pigmented plaques are dark-colored, scaly lesions that may be seen on the abdomen and typically only affect Miniature Schnauzers and pugs. They are caused by the Chipapillomavirus. In Miniature Schnauzers, these warts may not go away on their own and can become malignant.
Dogs cannot pass papillomavirus to humans, only to other dogs. Human papillomas are only transmitted between humans.
Papillomas generally do not require medical treatment unless they become irritated, infected, or grow large enough to cause discomfort. In most cases, warts go away on their own as the dog's immune system learns to fight the virus. However, some dogs will need medical intervention.
Potential treatment of warts in dogs involves cryogenic removal (freezing), surgical excision, or laser surgical removal. In some cases, these warts may return after removal. Interferon injections are sometimes used to treat warts. A cream may be recommended to treat canine papillomas. The use of CO2 laser therapy has shown success in some studies. Vaccination may be available for resistant cases.
Your veterinarian may refer you to a specialist, such as a veterinary dermatologist for treatment of severe canine papillomas.
How to Prevent Warts
Since dogs develop warts after contracting a virus from another dog, the only way to prevent them is to keep your dog from coming into contact with other dogs that have warts. This may happen at a dog park if someone brings a dog with warts to the environment.
Canine papillomavirus can live in the environment, so you should wash any bedding, toys, and bowls shared by other dogs know to have warts.
If your dog has papillomas, do not allow your dog to come into contact with other dogs until all warts have gone away on their own. Ask your veterinarian for advice on when it is safe to let your dog be around other dogs.
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Levy BJ, Sample SJ, Yuan H. Multimodal treatment of a dog with disseminated cutaneous viral papillomatosis. Vet Dermatol. 2018;29(1):78-e31.
Successful treatment of persistent oral papilloma using CO2 laser therapy. Aesculight.
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