You might think you're hallucinating. Your dog's skin has become reddish and flaky, and now it looks like his skin flakes are moving of their own accord. Relax -- you aren't losing it. Your dog is likely afflicted with cheyletiellosis, known colloquially as walking dandruff. He probably picked up these unwelcome visitors from exposure to an infested dog at a boarding kennel, a doggie daycare, a grooming or training facility, or the dog park.
Cheyletiella mites are the culprits behind walking dandruff. Not only do they affect canines, but these very contagious little pests could also start your dandruff moving. It can spread to cats, rabbits and other household pets. Mites feed on the outer layer of the skin, pushing underneath so that skin flakes seem to move. Relatively large, the mites can be seen with the naked eye. They lay eggs on the host mammal's hair shafts. Mites live on the host for between three and four weeks but can survive for up to two weeks off the host. That means dogs don't need direct contact with another canine or pet to become infested.
To Itch or Not to Itch
While all dogs with cheyletiellosis experience flaky skin, other symptoms vary. The mite causes some dogs to itch like crazy, while other never seem to scratch. Most of the flaky, reddened skin appears on the trunk, although mites might infest the face and even hide out in the dog's nose. Dogs who scratch a lot often develop crusty lesions, which can develop secondary bacterial infections. Other signs include small swollen areas within the flaky skin.
Treating Moving Dandruff
Your vet diagnoses cheyletiellosis by taking a skin scraping from your dog or by placing sticky tape on the affected region to pick up mites. After diagnosis, she'll prescribe special medicated shampoo or dips to kill off the parasites. If your dog takes a monthly heartworm preventive containing ivermectin, cheyletiellosis shouldn't be an issue. This broad-sprectrum wormer gets rid of this and other mite species. Every dog in your household should be treated for mites, even if asymptomatic.
In conjunction with physically treating your dog, you must eradicate mites from the animal's environment. That involves frequent vacuuming and washing or disposing of bedding and toys. You can apply flea spray designed for household use in areas frequented by pets, as it will get rid of mites.