Not every animal or human who touches infected animals or objects will become infected; the age, immune status, skin condition and grooming habits of the recipient influence if the fungus is actually able to grow and infect. Young, old and those with suppressed immune systems are most at risk. In animals, the classic ringworm lesions are patchy areas of hair loss and scaliness, usually with very little inflammation or redness. It is not usually itchy. In humans, the lesions depend on the type of fungus and the location of the body. Most commonly, lesions are red, raised and itchy, sometimes scaly.
Ringworm is best diagnosed by doing a fungal culture — adding some hair and skin scraping material to a tube of growth media (culture) and seeing what grows on it. This can take several days to a few weeks. A quick “in office” test is the Wood’s lamp test, using an ultraviolet (black) light in a darkened room to see if the affected area will fluoresce to a yellow-green. It should be noted that not all ringworm fungus infections will fluoresce. Dander or other non-ringworm conditions may fluoresce, so interpretation can vary. A fungal culture is needed for definitive diagnosis of ringworm.
In some cases, ringworm will resolve on its own. Ringworm treatment varies with the severity of infection. In mild cases, a reputable topical treatment should be sufficient. Shaving the affected areas is also helpful. For more advanced cases, your veterinarian may prescribe oral anti-fungal medications in addition to the topical treatments. Oral medications are generally reserved for severe and/or chronic infections and can be expensive and with side effects. Please speak to your veterinarian about what treatment is best for your pet’s condition, age, and general health status.
Ringworm can survive in the environment up to 18 months if the conditions are right. This fungus is also very contagious between animals – humans and pets alike, so environmental decontamination is necessary. Killing the fungus and ridding it from the environment is difficult. Here are some tips to help.
- Confine contaminated pets to one room.
- Vacuum deeply and often, taking care to dispose of vacuum bags or empty canisters.
- Dispose of rugs and carpets if you can.
- Wash or dispose of all bedding and toys.
- Wash applicable surfaces with a reputable ringworm treatment.
- Repeat these steps often until problem is resolved.