Ringworm in Cats

Ringworm (dermatophytosis) is a highly contagious fungal infection that affects the skin, nails, and hair of cats, dogs, and humans.  Because the infection can be transmitted from a cat to other cats, dogs, and humans, it's important for pet owners to know the signs of an infection in order to get it treated as quickly as possible.

Signs and Symptoms

Three species of fungi are responsible for causing ringworm in cats: Microsporum Canis, Microsporum Gypseum, and Trichophyton Mentagrophytes.  The most telling sign that a cat has ringworm is the presence of flaky bald patches with red centers.  These lesions are most commonly found on a cat's head, forelegs, chest, and along the ridge of the back, according to VCA Animal Hospitals.  Other cats may present with circular, thickened areas of skin with hair loss.  WebMD asserts that sometimes a cat with a mild case of ringworm will only present with dandruff or localized red areas.  In severe cases, ringworm can spread all over a kitty's body.  

Infection of the cat's claws occasionally occurs as well.  An infected cat's claws may become rough and uneven or deformed.

Some cats may have ringworm but show no clinical signs of the infection; these cats are known as asymptomatic carriers.  Up to 20% of kitties with ringworm are asymptomatic carriers, according to Cat World.  

WebMD asserts that kittens under one year of age and senior cats are most susceptible to the infection as are longhair and immunocompromised kitties.  

Transmission

Ringworm can be transmitted through direct contact with an infected animal or human or indirectly through touching contaminated surfaces or handling contaminated objects.  According to VCA Animal Hospitals, fungal spores can remain on objects, such as furniture, brushes or combs, food and water bowls, and bedding for up to 18 months.  

Coming into contact with an infected animal or person or with contaminated objects does not always lead to infection.  In general, healthy adult people do not develop an infection unless they have a cut or other break in the skin.  Those who are most at risk of developing a ringworm infection are children, elderly individuals, people with skin sensitivities, and those with weak immune systems.  

Diagnosis

A Wood's lamp (a special ultraviolet lamp) can be used to diagnose ringworm caused by Microsporum Canis, as it gives off a yellow-green fluorescence when the skin is examined in a darkened room.  However, the preferred method for diagnosing ringworm is through a culture.  Skin and hair scrapings are taken from the kitty and sent to a laboratory.  It may take a few days to a few weeks to grow a positive culture.  

Treatment

According to VCA Animal Hospitals, ringworm is self-limiting in a lot cats, with the infection clearing up in three to five months.  However, treatment is always recommended in order to minimize the spread of the infection to other animals and humans.  Treatment is most often a combination of topical ointment and oral medication.  However, for treatment to be successful, environmental contamination must also be dealt with.  

Traditionally, the oral medication, griseofulvin, has been utilized in the treatment of ringworm; however, newer medications, such as terbinafine and itraconazoleare are sometimes preferred as they have fewer side effects.  Treatment with topical ointment and/or oral medication is typically required for several weeks or months.  Periodic cultures will be taken during the course of treatment.  Treatment will be necessary until two consecutive cultures come back negative for ringworm.  

If there is more than one pet in the house, you may want to separate the infected pet and try to treat him or her alone.  Other times, it's best to treat all the pets in the household for ringworm.  Your vet can help you determine the best course of action for your specific circumstances.

Eliminating fungal spores in the environment is also required in the treatment of ringworm.  Use a 1:10 or 1:100 bleach to water solution to disinfect surfaces.  Additionally, damp mopping and vacuuming of floors should be done as often as possible to remove fungal spores from floors.  To remove fungal spores from furniture, use your vacuum or an electrostatic cleaner.  VCA Animal Hospitals also suggests restricting an infected cat to easy-to-clean rooms of the house.  

Utilizing these strategies can increase the likelihood of successful treatment and minimize the likelihood of the infection spreading to other members of your family.  

Sources:

VCA Animal Hospitals: Ringworm in Cats

WebMD: Ringworm in Cats

Cat World: Ringworm (Dermatophytosis) in Cats