Welcome to the strange world of demodectic mange, the scabby, sometimes itchy condition that affects a select few of our feline friends. Caused by a microscopic mite of the Demodex family, this condition may be rare, but it can drive cats and their owners crazy.
In this article, we’ll dive into the nitty-gritty of demodicosis, from causes to treatments, and everything in between. Let’s dive right in and talk about how you can help your cat overcome demodectic mange!
Overview of Demodectic Mange in Cats
Demodectic mange in cats is a skin condition caused by an overgrowth of mites in the Demodex family. These mites live in the hair follicles, oil glands or superficial skin layer of cats. Although they are present in low numbers in normal cats, an overgrowth can lead to hair loss, scaly skin, and itching.
Interesting Facts About Feline Demodex Mites
- Demodex mites have 8 legs and an elongated body.
- They eat the oil produced by glands in a cat’s skin.
- You can’t see them without a microscope since they are about 1/10 the size of the head of a pin.
- Disease caused by these mites is rare in cats and is often confined to the ear canals.
- Demodectic mange can affect cats of all ages, but it is more common in elderly cats.
- The mites are not contagious to humans or other species of animals.
- The prognosis for recovery is good for most cats with proper veterinary care.
Root Causes of Demodectic Mange in Cats
There are three species of Demodex mites that can affect cats: Demodex cati, Demodex gatoi, and an unnamed species. D. cati overgrowth in cats is often the result of immune-compromising conditions such as diabetes mellitus, Feline Immunodeficiency Virus, Feline Leukemia Virus or steroid medication therapy.
It’s important to note that D. cati is not contagious, but D. gatoi is contagious between cats through casual contact. D. gatoi mite infestation is more common on the Gulf Coast of the United States.
No particular cat breeds are known to be more susceptible to getting demodicosis.
Recognizing the Symptoms
Clinical signs of feline demodicosis are caused by inflammation in the skin as a reaction to the mites. General symptoms include
- Hair loss
- Skin redness
- Thickened skin
- Scaley skin appearance
- Sometimes itchiness
Symptoms of D. cati include hair loss, skin redness, and crusting mostly on the head.
D. gatoi symptoms include over-grooming, severe itchiness, red skin, and scaling along the top of the body, the belly and legs. In some cases, it may cause lip sores that look similar to those caused by eosinophilic granuloma complex (rodent ulcers).
D. cati infestations do not usually cause itchiness. D. gatoi mites make some cats very itchy, probably due to a hypersensitivity reaction. Other cats have no symptoms even when they have many D. gatoi mites on their skin!
How Veterinarians Diagnose Demodicosis
Diagnosis of demodicosis is made through a skin scraping, hair pluck, skin biopsy, or fecal test. Since some types of Demodex mites are difficult to find, vets sometimes make a diagnosis based on a cat’s response to treatment.
Demodicosis cannot be definitively diagnosed based only on a cat’s symptoms. There are several diseases with similar symptoms, such as food allergies, pollen allergies, contact allergies, rodent ulcers, ringworm, Otodectes ear mites, Cheyletiella mites, pemphigus foliaceus, and behavioral-based fur loss.
It’s essential to work closely with a veterinarian to accurately diagnose and treat any skin disease.
Treatment Options and Considerations
There are no FDA-approved treatments for feline demodicosis, but veterinarians have found a few methods that work for most cats. Treatment options include
- Topical lime sulfur
- Oral ivermectin or milbemycin
- Topical Advantage Multi® for cats
- Oral Bravecto®
- Topical Revolution Plus®
Treatment for D. cati should be continued until your vet does two negative skin scrapes one month apart. Treatment for D. gatoi should continue for six weeks.
In some cases, demodicosis will respond well to treatment only to recur later. Treating underlying disease and modifying immune-suppressing drug therapy may be necessary to get the skin condition under control. It is important to work closely with a veterinarian to manage this sometimes complex disease.
The Outlook for Cats with Demodectic Mange
Fortunately, this disease is not fatal! The prognosis is good with proper treatment and monitoring. Some cats with D. cati need ongoing treatment to keep mites under control.
Prevention Strategies for Cat Owners
When D. gatoi occurs in multi-cat homes, it is essential to examine and preemptively treat asymptomatic cats. If possible, keep affected cats isolated away from uninfected cats.
It is not necessary to treat your home for Demodex mites as they cannot survive in the environment and are not known to be passed from environmental sources.
- Feline demodicosis is a skin condition in cats caused by an overgrowth of microscopic Demodex mites that live in a cat’s hair follicles, oil glands and skin.
- Demodectic mange is a rare problem, with only about 4 in 10,000 cats affected, and it is often confined to the ear canals.
- Cats with a compromised immune system are more susceptible to developing skin symptoms from Demodex mites.
- D. cati is not contagious, but D. gatoi is contagious to other cats through casual contact.
- Topical and oral treatments prescribed by a veterinarian are effective at controlling the disease in most cases.
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