Ringworm, despite its misleading name, is not caused by a worm but by a fungal infection. These fungi, known as dermatophytes, feed on keratin, a protein found in the outer layers of skin, hair, and nails. Humans can contract this infection from cats, as ringworm is a zoonotic disease.
How Ringworm Spreads from Cats
Ringworm spreads primarily through direct contact with an infected cat. The fungal spores can reside on the cat’s fur and skin. Cats, especially kittens, are common carriers, and some may even carry the fungus without showing any visible symptoms.
Beyond direct contact, indirect transmission also occurs through contaminated surfaces. Fungal spores can be shed into the environment and remain viable for extended periods on objects like bedding, grooming tools, furniture, and carpets. Touching a surface an infected cat has been on can lead to human infection.
Identifying Ringworm Signs
Recognizing ringworm involves observing specific signs in both humans and cats. In humans, the infection often presents as a red, itchy, circular rash with raised edges and a clearer, scaly, or bumpy center, giving it the characteristic “ring” appearance. The rash can vary in color depending on skin tone, appearing red on lighter skin and reddish, purplish, brown, or gray on darker skin.
If ringworm affects the scalp, it can lead to patchy hair loss, and on nails, it may cause discoloration, thickening, or cracking. Symptoms appear between 4 to 14 days after exposure to the fungus. In cats, signs of ringworm can be more varied, including circular patches of hair loss, often on the head, ears, or legs.
Cats may also exhibit scaly or crusty skin and broken hairs. The affected areas can appear red and sore, with a crusty covering. While the face, ears, tail, and paws are common locations for lesions, some cats, particularly long-haired breeds, can be carriers without displaying any obvious symptoms.
Managing and Preventing Ringworm
If you suspect ringworm in yourself or your cat, seeking medical attention for humans and veterinary care for cats is advisable. For humans, mild cases of ringworm on the skin are treated with over-the-counter antifungal creams, ointments, lotions, or powders applied for two to four weeks. Scalp infections, however, require prescription oral antifungal medication taken for one to three months, as topical treatments are not effective for these cases.
For cats, treatment involves a combination of topical antifungal medications applied to the skin and oral medications, with treatment lasting a minimum of four to six weeks, or longer. Environmental decontamination is also an important part of managing ringworm in a household. This includes regularly cleaning and disinfecting areas the infected cat frequents, such as bedding, toys, and furniture.
Preventing ringworm transmission and recurrence involves good hygiene practices, such as thorough handwashing after handling pets. Isolating new pets until they are cleared by a veterinarian can help prevent the introduction of ringworm into a household. Avoiding sharing personal items like towels, combs, or clothing can also help limit the spread of the fungus.