How Is Ringworm Diagnosed?

Our dermatology experts can perform a Wood's lamp examination, microscopic examination, fungal culture, or a PCR test.

"A Wood's lamp examination involves using an ultraviolet light to examine your cat’s fur. By doing so, some infected hair shafts may fluoresce a yellow-green or apple-green color, although not all cases will glow under the lamp," says Dr. Soheyl.

Our vets may also obtain samples of hair and skin scrapings from your cat for direct microscopic examination. From here, we can check for fungal spores or hyphae, the branching structures of fungi, but this rapid test has limited sensitivity of roughly 59%.

"The most definitive way to diagnose ringworm in cats is through a culture. This will be done in our in-house laboratory," says Dr. Soheyl.

Our vets will culture samples of hair and skin scrapings on dermatophyte test medium. The culture is incubated in the dark for 10-21 days to allow the fungus to grow. This will allow us to accurately identify the species.

A PCR test is also an option, as it's highly accurate and offers over 95% sensitivity. It typically delivers results in 1-3 days. A skin biopsy may also be considered for unusual or atypical lesions if another condition is suspected.

Ringworm Treatment

A combination of oral medications, topical therapy, and strict environmental decontamination is required for ringworm treatment. The process takes 6 weeks or more, depending on each cat's case.

Oral Treatment

Common oral medications include itraconazole and terbinafine. These are efficient at treating moderate or widespread infections and preventing the ringworm fungus from reproducing.

Topical Therapy

For topical treatment, our vets may prescribe lime sulfur dips or shampoos containing miconazole and chlorhexidine. Whole-body rinses and shampoos are effective at killing spores from the entire cat, keeping them treated topically.

We may also provide creams and ointments to apply to affected areas. Topical antifungal medications are highly effective, especially for localized lesions.

Home Decontamination

Your cat's environment should also be sanitized and decontaminated to prevent recurrence. Environmental contamination is a major roadblock for full recovery.

Recovery Timeline

Treating ringworm in cats takes patience and consistency. Here’s a general recovery timeline to help guide your expectations:

• Weeks 2 to 4. Your cat will gradually show signs of recovery during this time, especially when proper treatment is given, though visible lesions often still take several weeks to fully clear.

• Weeks 5 to 6. Some cats may have almost fully recovered by this point, while others need more time for healing. Do note that it’s important to follow the full course of treatment.

• Weeks 6+. The next weeks will be for confirming healing. In many cases, treatment is stopped only after two consecutive negative fungal cultures, as directed by our vets.

Even after the visible symptoms disappear, some cats may still carry spores, which is why repeated fungal testing is recommended before reintroducing your cat to other pets.

How to Prevent Ringworm in Cats

Since ringworm spores can remain in the cat’s environment for extended periods of time, good cleaning and maintenance practices are essential.

Similar to treatment, home cleaning is crucial. Wash your pet's bedding, blankets, and pillows at least once a week with hot water and a strong detergent. Vacuum carpets and surfaces regularly. We also recommend disinfecting hard surfaces with a diluted bleach solution or products with chlorine bleach.

Infected hairs from cats can shed spores into the home, so keep your cat isolated in a room that's easy to clean. Keep your cat indoors at all times.

For their personal hygiene, bathe your cat once every 4-6 weeks using a vet-approved shampoo. However, remember to avoid overbathing them. You should also feed your cat a high-quality diet to keep their skin and coat healthy.

“Ringworm is a stressful experience for our cats. The health of their skin is a big part of their overall health and happiness.”

- Dr. Paulina Czerska

Frequently Asked Questions

How long will a cat have ringworm?

With consistent veterinary advice and treatment, ringworm may last for just 4-6 weeks. Severe cases may take several months.

Are some breeds prone to this condition?

Himalayan and Persian cats are known to be prone to ringworm because their skin has a harder time fighting off the fungus. Long-haired cats with thick coats are also at risk since their coat can easily trap fungal spores.

Can ringworm resolve on its own?

Technically, yes. However, it may take anywhere from 3 months to a year for a cat's immune system to clear the infection entirely. During this time, your cat will remain highly contagious to humans and other pets.

Is this painful for cats?

It's not typically painful, but affected cats do experience intense irritation and itching. Ringworm causes dry, crusty skin, which can be very uncomfortable.

Is it possible for cats to have ringworm without showing symptoms?

Yes, some cats may not show any symptoms. They're known as asymptomatic carriers, since they can still harbor and spread the fungal spores.