Thanks for your help. The mite is also infectious to dogs and cross infection between cats and dogs commonly occur. Mites may transiently infect humans also. Mites generally reside inside the ear canal ,usually near the opening to the external ear, but may be found on the outside of the ear, head or the body. Mites feed on lymph and other cellular fluids on the skin and produce a pronounced hypersensitivity reaction.
Several treatments are on the market for mites.
After the ears are thoroughly cleaned sulfur, rotenone, pyrethrins and thiabendazole are effective topically against mites. Commercial preparations often contain a topical anesthetic to reduce pain and a corticosteriod to decrease inflammation. I have seen few side effects using this treatment but it is an off label use of the drug and you should consult your veterinarian before you try it. The topical treatments with higher percentage of rotenone and pyrethrins can be toxic to cats and most labels say not to use them on cats. The reactions I have seen are dialated pupils, incoordination and in one case death.