Mange is commonly thought of as a skin condition of dogs, sarcoptic mange often depicted affecting dogs on charity adverts with thickened skin and no hair. The other type of mange is called demodectic mange, caused by the demodex mite. This also causes itching and hair loss but to a slightly less dramatic level. But can mange affect our feline friends, and how does it cause a problem?
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Can cats get mange?
Both types of mange can affect cats with a feline specific variation of the Sarcoptes and Demodex mite. Looking at demodectic mange, the three species known to affect cats are Demodex gatoi, Demodex cati and an un-named third species. D. cati is more common in an immunosuppressed animal, such as a cat with an underlying virus such as feline leukaemia virus and rarely affects healthy animals. It can also be seen with the common co- morbidity of hyperthyroidism. D. gatoi is more commonly seen in multi- cat households; as it seems to be able to be transmitted from cat to cat in adulthood, unlike D. cati.
What happens when cats get mange?
Clinical signs vary and will depend on the type of demodex mite causing the infection. In a D. cati infection the most commonly affected areas are the ears and face and can be seen particularly around the eyes. The affected areas are red, itchy and lose hair. They can also affect the ear canals and cause excess wax formation and head shaking. In D. gatoi infection clinical signs are less specific and can often present as overgrooming around the trunk and ventrum, resulting in hair loss.
How is demodex diagnosed in cats?
D. gatoi can be challenging to diagnose definitively. The most successful way to diagnose is from skin scrapes taken from multiple areas; including areas that have not been overgroomed. This can often be done without sedation (depending on the temperament of the cat!) with your vet carefully using a blade and some microscope slides. These will either be examined in house or sent to an external laboratory for analysis. A test called a tape strip can also be used for superficial infections, involving using a piece of tape on alopecic areas.
Even if the scrapes and tape strips come back negative, this does not always 100% rule out a demodex infection. Therefore treatment for demodex may still be recommended. D. cati is more readily found on deep skin scrapes so a positive finding with consistent clinical signs can allow a diagnosis. If the demodex is manifesting as excessive ear wax, a sample of the wax may be taken and examined under the microscope. Another way to diagnose an infection is through a positive response to treatment.
Treatment for demodex in cats
There is no licenced treatment for demodex in cats. But treatment options include topical treatments of isoxazoline products licensed for other uses in the species. Lime- sulphur 2% dips done once weekly for 4 to 8 weeks have also been found to be effective; but can be challenging in harder to reach areas such as the face. Treating any concurrent disease is also important, such as any topical infection secondary to self- trauma, or topical ear treatments for additional ear infections. Unlike with flea infections however, demodex cannot survive away from a host. So you don’t have to worry about treating your home.
Demodex can be confusing to diagnose and treat and depending on the type of demodex it can also be an indicator for an underlying disease process. Because of this, as well as the discomfort and skin irritation it can cause for your cat, it is important to see your vet promptly if you suspect an infection.
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