Ringworm in pets

Skin issues are one of the most common reasons for taking pets to the vet.

Skin problems is a wide subject and these cases can be complicated and challenging for the vet. Having a skin problem often suggests the existence of an underlying problem in the body, usually not even directly related to the skin itself. 

One of the more straightforward skin diseases is ringworm infection, which is not, as its name suggests, caused by a worm, but by a fungal infection.

The fungi responsible for the infection are known as dermatophytes. 

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. The lesion can be solitary.

A case of of multiple lesions is considered systemic and is called generalized dermatophytosis. 

The disease is highly contagious. The disease transmission occurs through direct or indirect contact with an infected animal. Indirect contact means contracting the disease by touching objects that the infected animal has touched; such as bedding, brushes or grooming equipment, furniture, rugs, etc.

Human can also get infected with ringworm by getting in contact with an animal that carries the fungi.

All animal are susceptible to ringworm infection. Among household pets, the disease is most common in cats. Infected dogs generally have a skin lesion at the site of the infection.

Interestingly though, not all cats that carry the fungi will show signs of skin lesions. Cats can be “silent carriers” and spread the disease without suffering from it. Not every animal or human who touches infected animals or objects will become infected.

The disease development depends on one’s age, immune status, skin condition and grooming habits. All these influence the fungus' ability to grow and infect.

In both animals and humans, young, elderly and those with a compromised immune system for any reason, are most susceptible to the infection.

Despite the fact that the disease is transmissible from pets to humans, this is not a reason to get rid of your pet. Ringworm is a treatable condition in both animals and humans.

The diagnosis for ringworm in animals is fairly simple. In about 30 per cent of the cases, looking on the lesion with a special ultraviolet light (also called wood’s lamp) in a dark room, will show a typical green fluorescence. Ringworm confirmation is done by a culture.

The veterinarian collects a sample of hair and scales from the lesion and places it in a special, small jar known as the culture media. Placing the jar in a dark place and the culture media provide the optimal condition for the fungus to grow and thrive.

This test is very easy to perform. It is affordable, non invasive, and does not require anesthesia or sedation. The only disadvantage of this test is that the results are not given immediately.

It can take for the fungal colonies up to 21 days to develop, even though, from my personal experience, usually within 5-7 days we get a good idea if the result is positive. 

If the lesion is solitary, the infection may be self limiting and may eventually disappear without treatment.  Generalized cases (multiple lesions) require treatment.

The treatment can be done topically in a form of a medicated shampoo. Some cases require systemic treatment by oral medication.

Your veterinarian can guide you through which course of action is best recommended for your pet’s condition.

Gathering information about your pet, and the physical exam findings will also help your veterinarian in assessing whether the condition has developed due to other underlying problem that has weakened your pet’s immune system.

If you recognize in your pet a single or multiple areas of hair loss, with or without crusting and scaling that are usually not itchy, take it to be examined by your vet. 

If your pet was diagnosed with a ringworm infection, thorough cleaning of the house and the dog’s bedding and equipment is also necessary for the elimination and prevention of reinfection.

Also consult your GP about treating the human members of the family.  

More Dr. Oz's Vet Advice articles

About the Author

Dr. Moshe Oz owns Rose Valley Veterinary Hospital, a small animal veterinary practice in West Kelowna.

Dr. Oz has deep love and affection for animals. It was his childhood dream to become a veterinarian, a dream that he has fulfilled when he graduated with honours from KUVM,on 2006. Dr. Oz's special interest is internal medicine and surgery.

In his free time Dr. Oz enjoys training and racing triathlons, including the legendary Penticton's Ironman.

Dr. Oz can be contacted through his website: www.KelownaVet.ca

The views expressed are strictly those of the author and not necessarily those of Castanet. Castanet does not warrant the contents.

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