Download What is ringworm? How can my dog be infected? How do I know if

Ringworm
Ringworm is the common name given to a fungal infection also known as
dermatophytosis. Ringworm is not uncommon in dogs and if your dog has skin problems
it may have ringworm. The disease is highly contagious and can be passed on to
humans so if any signs develop it is important that you seek veterinary advice
immediately.
What is ringworm?
Ringworm is caused not by a worm but is a fungal disease resulting from infection with Microsporum canis.
It is one of the most common zoonotic diseases in pets, ie an infectious disease that can be transmitted
from dogs to other animals, including humans. Skin lesions, especially on the face, ears and limbs, and
nail bed infection are common signs. The appearance is variable and the signs can look very similar to
many other canine skin diseases. Patchy hair loss can also be present.
How can my dog be infected?
Ringworm is spread through contact with 'spores'. These are carried on hairs from infected pets and can
survive in the environment for months or even years. Many dogs that come into contact with the fungus will
not show any clinical signs. These animals can however carry the spores and pass these to other pets in
their household. Young dogs, less than 1 year of age, are most commonly infected; but older and sick
animals are also at risk. Some breeds, particularly small terriers, appear to have more chance of being
infected.
How do I know if my dog is infected?
Typically the disease affects the face and front paws. If infected, your dog may have patches of hair loss
and red, crusted areas on its face or paws. Scratching and chewing at hair may result in vomiting of
hairballs or constipation. Sometimes nails are affected resulting in nail loss or thickening. More rarely sore
or ulcerated areas of skin are present.
What tests will my vet do?
If your vet suspects that your dog is infected they will want to take hair plucks and samples of coat
brushings to confirm the diagnosis. Your vet may use an ultraviolet lamp (Wood's lamp) to examine your
pet's hair - under ultraviolet light some types of ringworm appear to glow apple green. This is not a definite
diagnosis but will identify hairs that can be used for further examination. A rapid test is to examine the
hairs under the microscope to identify fungal spores. It may be necessary to try to grow ringworm from
samples and, because the fungus grows slowly, this can take several weeks for a confirmation of
diagnosis. To avoid delay treatment may be started while waiting for results of tests.
How can ringworm be treated?
Although signs of ringworm will resolve in most healthy adult cats within a few weeks without treatment,
treatment is usually recommended because of the risk to other pets and to people. Ringworm can be
treated with antifungal agents such as griseofulvin, ketoconazole or itraconazole as prescribed by your vet.
Clipping your pet (using scissors reduces skin trauma) may reduce the risk of your pet spreading the
disease. Your vet may recommend application of an enilconazole or chlorhexidine dip or a shampoo twice
weekly for 6-10 weeks or until coat brushings are negative for culture.
Gloves and protective clothing should be worn to prevent the spread of infection when treating your cat.
If one pet in a household is diagnosed with ringworm then all other animals (including humans) need to be
examined for signs of infection. It may be necessary to treat all in-contact cats and dogs by the
administration of oral medication and by applying a topical medication directly to the hair and skin.
Treatment should continue for 2 weeks after the lesions have disappeared or until two samples taken a
week apart are negative on fungal cultures.
How can I prevent other pets from being infected?
Fact sheet no.: 284714
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Ringworm
Infected animals should be isolated and confined to one room to reduce the contamination in other parts of
the house. Avoid grooming infected animals until treatment has finished. Contamination by hair and scale
can be reduced by vacuuming contaminated rooms and pet bedding. Vacuum bags should be disposed of
by burning. Floors, worktops, litter trays, bowls and cages should be disinfected at least twice a week with
1:10 dilution of household bleach and allowed to dry before giving pets access again. Disposable cloths
should be used for cleaning and all grooming equipment should be disinfected.
What does ringworm look like in people?
In people ringworm usually starts as reddish, scaly patch of skin. The areas may be itchy or dry and
eventually, it may begin to resemble a ring or a series of rings. The skin lesions may be raised with bumpy
borders around a scaly centre. If lesions develop in haired areas of skin the hair loss occurs, usually in a
circular pattern. If you develop any skin lesions then you should see a doctor as human lesions will need to
be treated appropriately.
If you want any other information on health issues concerning your dog please contact
Hook Veterinary Centre 01256 764771 and we will be happy to advise you.
Fact sheet no.: 284714
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