You should seek the advice of your veterinarian if your pet is ill as only he or she can correctly advise on the diagnosis and recommend the treatment that is most appropriate for your pet.

The are many different arthropod parasites that can cause skin disease in animals. One type of mite (Cheyletiella) causes a lot of scaling (dandruff) and itchiness.

Cats, dogs and rabbits can be affected by many types of Cheyletiella  but the 3 most common forms of the Chyletiella mite are :

• C. blakei - most often seen on cats
• C. parasitovorax - most often seen on rabbits
• C. yasguri - most often seen on dogs

These mites live on the surface of the skin and lay their eggs attached to hair shafts. They are quite big, have 4 legs and can be seen with a magnifying glass. They are white, and when they move they give the appearance of moving scurf - hence the popular description of the disease "walking dandruff" !

These mites live their whole life span (21- 35 days) on the animal although they can survive for up to 14 days in the environment. They are usually transmitted by direct contact with other animals but occasionally from contact with mites in the environment.

Signs of this mite infestation are :

• Dandruff formation along the back - especially in dogs and rabbits, but also in cats
• Itchiness - usually mild
• The formation of crusty swellings in the skin (called papules)
• Inflammation of the skin (reddening)
• Hair loss may occur in some cases
• Some cats develop multiple scaly papules (so-called miliary dermatitis)
• Sometimes no signs are seen

Chyletiella can be transmitted to people and so this mite is a zoonosis. Typical signs are clusters of 3 itchy, red spots (papules) usually on the arms, trunk of the body and buttocks where the person comes into direct contact with animals, or where animals lie.

Diagnosis of this disease is based upon the signs, and identifying mites or their eggs in skin scrapings, on sticky tape samples or in brushings from the coat. Mites and eggs can also be found in faecal flotation tests. Like most mite infestations a negative sample does not necessarily mean that they are not present - just that the sample missed them, so multiple samples need to be taken.

All animals in a household should be treated, and a variety of different treatments have been recommended for Chyletiella. Most flea preparations will probably kill the mites, but no products are specifically licensed for use in Cheyletiellosis. Various authors have recommended different treatments including :

• Amitraz dips every 2 weeks for 3 treatments (dogs only)
• Fipronil - ("Frontline" - Merial) spot on for cats and dogs. Can not be used in rabbits.
• Ivermectin 0.2-0.3g/kg by injection every 2 weeks for 3 treatments (cats, rabbits and some breeds of dog)
• Lime sulphur - immerse once weekly
• Permethrin - rabbits (only use with care in cats)
• Pyrethrin - once weekly
• Selenium sulphide shampoos every week for 5 weeks
• In addition to these the environment should be treated -  hoover and spray with anti-flea preparations.

Updated October 2013