Ringworm is a skin infection of the skin caused by fungus.  Many different varieties of ringworm exist.  Ringworm may be spread between pets (dogs, cats, rats) and people, however this is not always the case. People can pick it up elsewhere. If a human in the household contracts ringworm, they should consult a physician.  If an animal in the household is suspected of being the carrier, consult with your veterinarian.

There is no longer a vaccination against ringworm, but there are treatments once a problem is recognized.

An infected animal may (or may not) display a lesion.  Lesions typically present as a patch of hair loss with dry, crusty skin, often in rings.  Small local lesions can be treated with topical antifungals.   If the animal has a generalized rash, then systemic treatments such as oral antifungals are often necessary.  Lime Sulfur dips are also helpful in eliminating generalized or asymptomatic ringworm.

Occasionally, an animal will be an asymptomatic carrier, meaning they show no rashes or signs of ringworm, but they carry it on their skin.  The only way to confirm an asymptomatic carrier is to do a fungal culture.  This involves a bit of wait time as fungus usually takes a while to grow in culture (at least a week).

Prevention:  One more important aspect of ringworm is that, no matter where it started, environmental treatment is essential to prevent it’s continuing or recurring later.  You can treat the infected individual, but it does like to hang around the environment.  Multi-animal households tend to have this problem more often.  To clean and prevent the spread of ringworm, use diluted bleach (1:10 with water) on hard surfaces such as floors, counters, brushes, bowls,etc.  Frequent vacuuming cannot hurt.  Ringworm can occasionally aerosolize and hang out in air-conditioning filters, etc.  Hopefully you never get to that point, but some unlucky few have.