Dermatophytosis, or ringworm as it is commonly known, is a fungal skin infection which in cats is primarily caused by the agent Microsporum canis. The infection occurs in the keratinized tissues of the animal - ie.the hair, nails and stratum corneum (outermost layer of the skin). Ringworm is contagious between animals and is also considered a zoonosis, meaning that infection can be transferred between animals and humans.
Ringworm is typically seen more commonly in young kittens and immunocompromised cats (such as those with FeLV or FIV). It is thought that Persians and Himalayans are predisposed to developing ringworm infection. The clinical appearance of ringworm in cats can vary but typically is seen as focal hair loss, scaling and crusting of the skin. These lesions are most commonly located on the ears, face and extremities. Ringworm in cats is generally considered to cause little or no itching. Lesions can develop further in some cats.
Any suspected case of ringworm in your cat should be examined by your veterinarian. Simple diagnostic techniques exist which can help in determining the diagnosis.
Although ringworm is self-limiting in many cats, treatment is generally recommended to help hasten recovery and prevent spread of infection. This is especially important given that ringworm can be spread to humans from cats. Treatment of ringworm in cats involves treating the affected cat, all in contact animals and the environment. Owners are advised to wear gloves when handling and treating affected animals.
Treatment of the cat/s will vary depending on the severity of the case, but may include any or all of:
- Shaving the cat - this may be recommended in medium to long haired cats
- Topical application of antifungal cat shapoos or cat skin care solutions
- Systemic cat medication.
Treatment will need to continue beyond the visual resolution of symptoms until the veterinarian gives an all-clear based on length of treatment beyond clinical signs or successive negative fungal results. Remember, all in contact animals will also need to be treated.
The environment will also need to be cleaned to remove and hairs and spores which could aid in re-infection or transmission of the condition. Your veterinarian may provide a detailed environmental clean-up schedule aimed at removing and disposing of all hairs from the environment, including the cleaning of all brushes and bedding. Certain disinfectants and bleaches can be used to clean walls, floors and other surfaces.
Since ringworm (dermatophytosis) is a zoonosis, ie. can be transmitted from animals to humans, extra care needs to be taken whenever your animal is suspected or diagnosed with ringworm. As mentioned above, it is suggested that owners wear gloves when handling and treating affected animals. Your medical practitioner should be consulted to examine any lesions on humans and to advise on the best course of treatment. Young children and imunocompromised people are considered to be most at risk.