What Is Ringworm in Cats?
Ringworms or ringworm are the common names for dermatophytosis, a fungal infection that can affect a cat’s skin, hair, and nails.
The fungus, which feeds on dead cells, is not actually a worm. The name "ringworm" originated from the target-shaped lesion surrounded by a scaly ring seen in humans. It’s spread by direct skin-to-skin contact between people or between infected animals and people.
For ringworm in cats, this fungal infection is typically presented through hair loss and scaly lesions.
Symptoms of Ringworm in Cats
Symptoms of ringworm in cats include:
Thickened patches of skin
Circular areas of hair loss (may be patchy)
Broken and stubby hair
Scaly or crusty skin
Changes in fur or skin color
Inflamed areas of skin
Excessive grooming and scratching
Red or gray, scaly lesions (typically on the skin of a cat’s head, chest, front legs, and spine)
Dull fur
Rough, scaly, hardening of the base of the nails
Distortion of the nails
Nail infections (rare)
In some more severe cases of ringworm in cats, the skin lesions are raised and nodular. These are called granulomas and may frequently produce discharge.
Many cats, especially longhaired breeds, may have ringworm without any symptoms at all. These cats are called asymptomatic carriers.
Asymptomatic cats may still infect other pets or humans. It’s important to note that even though these cats don’t look sick, they may be highly contagious.
Causes of Ringworm in Cats
Ringworm in cats is spread through direct contact with the fungus. It may be passed by direct contact with an infected animal or person, the soil, or a contaminated surface. It’s rare—though possible—for ringworm to be spread through brushes, combs, and beds.
The fungal spore can survive and remain dormant on bedding, carpet, furniture, brushes, and/or other surfaces for up to 18 months.
Direct contact with a fungal spore causes infection, typically through open wounds (such as a scratch). However, immunosuppressed cats (cats with the decreased ability to develop a normal immune response) can get infected even without open skin.
Some predisposing factors for ringworm in cats include:
- Age—Kittens and older cats with compromised immune systems are at a higher risk for infection.
- Climate—Cats that live in warmer, more humid climates have a higher infection rate.
- Care—Cats who live in a densely populated environment (such as an animal shelter) or receive poor nutrition are at a higher risk for infection due to the contagious and resistant nature of this fungus.
- Health—Immune suppression can increase the risk of ringworm infection, especially in cats with feline leukemia virus (FeLV) or feline immunodeficiency virus (FIV).
The period between exposure to the fungus and the development of symptoms is usually between seven to 14 days, though with some cases, three to four weeks may pass before symptoms appear.
Treatment for Ringworm in Cats
Treatment for ringworm in cats is usually a combination of medication applied to a cat’s skin and oral medication. Treatment lasts for a minimum of four to six weeks. In some cases, several months of therapy is required.
Ringworm cultures are performed after the start of treatment to determine if the infection is still present.
Treatment is typically continued until two consecutive negative ringworm cultures are obtained, usually two to four weeks apart.
Topical Therapy
Topical treatment for ringworm in cats is directly applied to the skin. The treatment directly kills fungal spores, which is important in preventing environmental contamination and helpful in preventing contamination to other animals. Topical treatment will usually continue for several weeks or even months depending on your cat’s diagnosis.
Oral Therapy
Oral therapy for ringworm in cats may be recommended for severe or difficult cases.
This treatment stops reproduction and spread of the fungal infection. Once treated, only the original fungus remains and can be removed with other treatment options.
Your veterinarian may prescribe one of the following:
ItraconazoleTerbinafine
Griseofulvin