If you’re anything like me as a groomer barely a week goes by without brushing over a wart! Well, what we call “warts” are actually lesions caused by the papilloma virus. These lesions – often referred to as Papillomas – are contagious between dogs, but not to people or to cats. As groomers we do not have to be concerned about becoming infected with warts from the dogs we groom, but we should all sterilize our equipment after brushing/clipping to avoid spreading the virus to another dog.

Types of Warts

Papillomas in older dogs can appear anywhere on the body, and they can start and stay small, or they can grow larger over time. While canine papillomas are usually benign and harmless, they often bleed if scratched or chewed, and may become infected. Uncommonly, they can malignantly transform to “squamous cell carcinoma”, which is a much more serious problem. If you notice what looks like a “wart” on an older dog, it is a good idea to watch it closely – if the lump grows, changes colour or shape or becomes infected, let your client know and advise them to see a veterinarian to examine their dog and to discuss the best way to address this condition.

Cutaneous papillomas

Warts can also occur in younger dogs from 6 months to 4 years of age – especially inside the oral cavity and in clusters around the eyelids, mouth, lips, tongue or muzzle. These masses often have a “cauliflower”-like appearance and begin as small, smooth pale nodules that progress to darker pedunculated masses with frond-like projections. (I do a schnauzer like this and he looks like he has a pout, but when I lift his front lip it is a mass of warts!) Any tumour involving the oral or ocular membranes can be spread by direct contact between dogs when they lick and greet one another. Young dogs are more likely to develop papilloma lesions because they are still immunologically naive and tend to romp and play more roughly than older dogs, causing damaged skin and mucous membranes. A number of skin conditions can be confused with warts, some of which are very serious so, good advice to you clients is to get all lumps and bumps checked out with their Veterinarian.


Scabs are better cleared off the wart and hair around the area clipped short to help the owner to keep the area scab-free and clean to prevent infection. Although Papillomas generally do not need to be treated for medical reasons, they may be removed if they cause the dog discomfort (often lameness when they grow between the toes or affect the foot pads), for cosmetic reasons, or if they bother the owner.