Contrary to what is implied by the name, ringworm, or dermatophytosis, is not a worm at all! It is in fact a fungal skin infection caused by a group of fungi called dermtophytes. These critters can cause a small, round lesion on the skin accompanied by hair loss, scabbing and sometimes (but not always), itchiness. These lesions can occur in both dogs and cats, however in kittens and animals that have a suppressed immune system secondary to other illnesses, the lesions can cover large areas of the body. Cats, being tricky creatures, are able to carry the fungi in their fur and spread it to other animals without being infected themselves!
Dermatophytosis can be quite difficult for your vet to diagnose. We may view the lesions with the use of a special blue light from a Wood’s Lamp, which may cause some dermatophytosis lesions to glow a very cool bright green color. Hairs around the lesion can also be plucked for a fungal culture and this sometimes gives us an answer. In severe cases, a skin biopsy may be recommended to diagnose the disease before treatment. Single lesions can usually be treated with a topical cream, but more widespread lesions may require medicated washes or oral anti-fungal medication. Infection can take weeks to months to clear and perseverance is very important.
Now, you may be thinking that just the thought of this is making you itchy. Well, so it should… dermatophytosis is a zoonosis, which is a fancy term for a disease that can be transferred to humans. Ringwood in humans is possible! Lucky for us, most healthy people who are affected tend to get single lesions that clear up fairly easily with topical treatments that your doctor can prescribe. However, if your pet has been diagnosed with dermatophytosis infection, good hygiene is absolutely paramount to prevent infection of the household humans.
Did you or your pet ever have ringworm? How was it treated? Tell us in the comments!