Causes of Walking Dandruff
Walking dandruff is the common name for a skin condition caused by infestation of a dog’s skin by tiny Cheyletiella mites. These mites burrow through the outer layers of the dog’s skin, causing irritation and mild to severe itchiness (pruritis) as a result of mechanical irritation. They produce irritating by-products as a result of dining on the dog’s skin and can also secrete substances that cause an allergic reaction (hypersensitivity) in the affected animal. Dogs, cats and rabbits usually become infested with different species of Cheyletiella mites. These mites are highly contagious between members of the same host species. However, dogs, cats and rabbits can become transiently infested with the Cheyletiella mites that normally populate other hosts. This happens through direct contact between an animal carrying the mites and a member of a different susceptible species (dogs, cats, rabbits or even people). For example, a human can become infested by Cheyletiella yasguri mites as a result of petting an infested dog, which is the normal host for that particular species of mite.
Since the mites that cause walking dandruff are highly contagious between dogs, the best way to prevent infestation is to avoid direct contact between infested and non-infested animals.
Walking dandruff can affect dogs of any age, breed or gender. This is considered to be a zoonotic condition, which means that Cheyletiella mites can be transmitted from affected dogs to people. When humans develop cheyletiellosis, they usually have an extremely intense itchy reaction and develop small raised, itchy red bumps on their skin that are known as “erythematous papules.” These raised red bumps tend to be most prevalent on the person’s arms, trunk, abdomen and buttocks. The effects of these parasites on people will resolve once the dog and its living environment are successfully treated.
Cocker Spaniels, Poodles and long-haired cats can be asymptomatic carriers of Cheyletiella mites, which means that they can be infested with the mites without showing any outward signs of itchiness or skin scaling. Asymptomatic or inapparent carriers can become the source of contagion to all other dogs, and to cats, rabbits and people, with whom they come into direct physical contact. Walking dandruff is becoming less commonly seen these days because of the increasingly consistent use of flea-control pesticides, which usually also kill the Cheyletiella mites.