Health - Ringworm
Ringworm in Cats
Symptoms and Treatment
Contrary to its name Ringworm is not a worm at all but a fungus called Dermatophytes. Dermaphtytes means 'plants
that live on the skin'. In the past, because of the circular lesions made by the fungi they were thought to be caused
by worms, hence the name ringworm.
The fungi live on the surface of the skin and in the skin follicles feeding on dead skin tissue and hair.
There are three different types of fungus that can cause ringworm but the most predominant ones found on cats
and dogs is Microsporum canis.
What does Ringworm look like on my cat?
The usual symptom is a round hairless lesion. The characteristic "ring" that we see on humans doesn't always appear
as a ring on cats. This lesion will grow in size and often become irregular in shape.
The fungi cause the hair shafts to break off and this results in patches of hair loss. Ringworm are commonly found
on the face, ears, tail and paws. The lesions are scaly and may or may not be itchy and often the skin is reddened
How does my cat catch ringworm?
Transmission can happen by direct contact with another infected animal or person. It can be passed from cats to
dogs and visa versa and from pets to humans and from humans to pets.
The fungal spores can live in the environment for a long time and can be found in carpets, bedding, grooming
equipment etc and can infect your cat when it comes into contact with them.
The incubation period is 10-12 days. This means that following exposure to the fungus, about 10-12 days will pass
before any lesions occur
In rare cases ringworm can be spread by contact with infected soil. The fungus can live for months in soil if the
nutrients are right.
Fortunately the spores are easily killed with a solution of bleach and water.
500mls of bleach to 4 liters of water.
Can Humans catch Ringworm from Cats?
You can contract ringworm by touching an animal with ringworm. Ringworm can spread while petting or grooming
cats. You can also get ringworm from cows, goats, pigs and horses.
Are all cats susceptible to ringworm?
Healthy adult cats usually have a resistance to ringworm. Young cats and kittens are more susceptible because their
immune system hasn't fully developed. Many cats are carriers of ringworm but show no symptoms. They can,
however, infect other animals or humans.
Diagnosis of Ringworm
To diagnose Ringworm your vet will need to do one of the following tests. It is not possible by just looking at the skin
to make the diagnosis.
An ultra violet lamp also known as a black light. Your vet may use this as 50% of microsporum canis will glow under
Your vet may look at part of the hair or skin from the lesion under a microscope.
Your vet may decide to take a scraping from the lesion and send it away to the laboratory to see what the culture
Is there a cure for Ringworm?
If no treatment is carried out, ringworm will run it's course in two to four months and the symptoms will resolve
themselves. However, treatment is recommended to save your cat from suffering any longer than necessary and to
cut down the period of time they are contagious
Your vet may prescribe Griseofulvin for your cat. It is an anti fungal drug that is used for pets with ringworm but it
does have some side effects so be sure to consult your vet before giving any medication. Griseofulvin inhibits fungal
Shampoos and Dips:
Lime sulfur dips are often recommended by your vet.
Dips should be given twice a week and can be performed either by your vet or at home. Please be aware that Lime
Sulfur will stain clothing and jewelry and will cause temporary yellowing of the cat hair. It also smells very strongly
of rotten eggs. Follow your vets instructions for mixing the dip.
Decontaminate the environment
Use bleach mixed at 1:10 on any surface that you can. It will kill 80% of the spores. Vacuum on a daily basis a
dispose of vacuum bags which will contain the spores. Steam cleaning of carpets and furnishings will also kill a
large number of the spores.
Don't forget your cat bedding or basket. Wash the basket down with a bleach solution and wash the bedding in
very hot water. Confine your cat to one room of the house to avoid spreading spores all over the house.