What is ringworm?

Ringworm is a fungal skin infection that can affect dogs and cats, as well as humans and many other animal species. Its official term is dermatophytosis and it is highly contagious – it can survive in the environment for years. It is called ringworm due to the characteristic circular skin lesions that the fungus creates – these are often found on the head, ears, front legs and along the back, although they can occur anywhere. Ringworm is most common in young, elderly or long-haired cats and dogs.

It can take a few weeks to clear the infection and if your dog or cat is affected then you must take precautions to avoid catching the infection yourself, although skin infection is more likely to occur if your skin is damaged.

What are the symptoms of ringworm in dogs & cats?

The symptoms can be quite variable in degree and can be very mild in some cases and severe in others. The typical symptoms of ringworm include:

• Crusty/scaly skin lesions that are often ring-like (these can be grey in some animals and red in others)
• Patchy hair loss
• Dandruff or scurf in the coat
• Skin lesions can be itchy

How is ringworm in dogs & cats diagnosed?

The vet is likely to be suspicious of ringworm based on an examination of your pet’s skin lesion(s). This will prompt them to run some tests to check for the presence of the fungus. There are various tests that can be used to diagnose ringworm, these include:

• Checking for fluorescence of the coat using a special UV lamp (Wood’s lamp).
• Taking a sample of the hair to look at under a microscope to check for fungal spores.
• Taking coat brushing samples and trying to grow the fungus on a special culture plate (this is the most reliable method but it takes 10 days to get a result).
• Running a special blood test (this is the newest way of testing for ringworm and gives a result in a few days).

How is ringworm in dogs & cats treated?

The treatment will normally take a few weeks to work but is generally successful. The treatment typically involves the following steps:

• Clipping of the fur around the patches of ringworm. This will help to reduce it spreading and will make the treatment more effective.
• Antifungal shampoo. A medicated bath is recommended 1-2 times a week until the infection has cleared, which can take a few weeks.
• Oral antifungal medication.
• Decontaminate the environment. Ringworm can survive in the environment for up to two years, so treating the house is very important. The vet can discuss this will you, but it normally involves regular cleaning with a diluted bleach solution, vacuuming and washing of bedding (or replacing the pet bedding if possible).