Microsporum Ringworm

Microsporum ringworm, a fungus that causes a skin infection called ringworm, can pass from animals to people. Characterized by skin lesions and, typically, small scaly patches that do not always form a circle, microsporum ringworm causes hair loss at the affected site. Ringworm mimics other skin infections, such as demodex, caused by a parasite.

  1. Origin

    • Microsporum ringworm occurs predominantly in cats

      The microscopic fungal organisms called dermatophytes that cause ringworm thrive and proliferate in hot, humid environments, and can linger in pet bedding or soil up to 18 months. Three fungus strains cause ringworm, but the microsporum strain almost always occurs in young cats, according to Long Beach Animal Hospital.

    Appearance

    • Ringworm skin infections invade the top dead layer of skin, and appear most commonly as a raised ringed rash with a scaly center. Balding at the affected area is common, and occasionally pustules form. Veterinarians believe nearly 20 percent of cats carry microsporum ringworm, but never show symptoms, according to Cat World.

    Considerations

    • Ringworm infects young cats under 12 months old, cats that have weakened immune systems and stressed cats. Cats acquire the disease by direct contact with infected animals or contaminated bedding or soil. The fungal spores responsible for ringworm can linger in bedding or soil for up to 13 months.

    Diagnosis

    • Veterinarians diagnose ringworm by a few methods. About half the fungal strains that cause ringworm will fluoresce bright green under an ultraviolet Wood's lamp or black light. Scraping the affected site and placing hairs taken from the cat into a solution to create a fungal culture will pinpoint the type of fungus. While a culture takes up to 10 days, the ability to diagnose the precise strain also reveals an accurate treatment.

    Treatment

    • Longhaired cats acquire ringworm more often than shorthaired cats. The typical treatment for ringworm includes clipping hair to improve the efficacy of a medicated bath and decrease the risk of spreading the infection. Veterinarians usually do the bath at the hospital using a lime solution every four to six days over two to four weeks. Cats should not be allowed to groom following a bath, using a cone collar over the head. Antifungal drugs may also be prescribed.