Pet ringworm is a fungal infection that can affect both cats and dogs. The most common cause of ringworm is the infection with Microsporum canis, Microsporum gypseum or Trichophyton mentagrophytes.
Ringworm is highly contagious to both humans and pets and is transmitted through spores that infect the skin and hair, objects and the soil. The spores can live in the environment for a ling time, waiting for another host, so complete cleaning of the pet's environment must go together with the treatment.
Ringworm has symptoms very similar to other skin conditions, so diagnosis by a veterinarian before starting any treatment is compulsory.
Symptoms of Pet Ringworm
The symptoms of pet ringworm are not specific, they indicate skin disease but do not point precisely to ringworm:
- Hair loss in circular areas mostly on the head but often on the legs, feet or tail, which is the single symptom that is specific to ringworm
- Small papules surrounding the area that has no hair
- The skin is scaly and inflamed inside these areas
- Acne on the chin
Diagnosis of Ringworm
As the visible symptoms of ringworm are difficult to differentiate from the symptoms of other conditions, once the veterinarian suspects your pet is affected by it, he will need to perform more tests.
A black light lamp, Wood's lamp, is sometimes used. The ringworm fungi are fluorescent under this light. However, this test is not 100% accurate, as some species of ringworm fungi do not glow under the lamp. Also, healthy animals can have fluorescent fungi on their coat and not have the infection.
The most effective method is a fungal culture that your local veterinarian can easily perform.
Pet Ringworm Treatment Options
Ringworm is highly contagious to pets as well as to humans. Having an infected pet will involve not only treatment of the respective pet but also preventative care for all the pets in the household and thorough cleaning of the environment.
Your options include topical or oral treatment:
- Small, isolated lesions can heal without treatment in up to 4 months (but the pet will be contagious during that period of time).
- Topical treatment involves clipping the hair around the lesions as close to the skin as possible. You will need to be extremely careful as the smallest injury will help the infection spread further. The most common topical solutions are miconazole cream, Lotrimin cream, 1% chlorhexidine ointment or dips in lime sulfur or antiseptics.
- Antifungal shampoos are recommended in order to keep the spreading of the spores under control.
- Vaccines for ringworm are available, but they can only be administered accompanied by treatment.
- Systemic treatment involves several oral medications. A preferred oral medication for ringworm is Griseofulvin, as it is administered together with food. This medication will be accompanied by regular blood tests, to watch for side effects (bone marrow suppression).
- Itraconazole and Ketoconazole are other options. If your pet is pregnant, you should notify your veterinarian when discussing treatment of ringworm, as some medications can interfere with pregnancy.
When having an infected pet, you should be cautious about always wearing gloves and washing your hands thoroughly after having touched the pet.