Otodectic mites are tiny insects that live in the ear canals and feed by piercing the skin. They are highly contagious to cats and dogs, but not to humans. Ear mites are the most common cause of ear symptoms in cats. Ear mites should be treated immediately using an treatment or cleanser. Commonly used products include Otomite Plus, Nolvasan Otic Cleansing Solution, and Eradamite.