can a cat get a cold sore

blank_pageThis sounds like an eosinophilic granuloma, which is fairly common in cats.  The cause is not well defined but is thought to involve some process in the immune system of the cat.  Eosinophils are a type of circulating white blood cell that are associated with allergic-type responses and they are usually found in these granulomas.  These granulomas can come and go on their own without any treatment, but they usually get to be swollen enough that treatment is advisable.  A long-acting corticosteroid is the treatment of choice.  These granulomas are not thought to be contagious.  It has also been suggested that they might be related to some form of stress in the cat's life.