Canine distemper is a contagious and serious viral illness with no known cure. The disease affects dogs, and certain species of wildlife, such as raccoons, wolves, foxes, and skunks. The common house pet, the ferret, is also a carrier of this virus. Canine distemper belongs to the Morbillivirus class of viruses, and is a relative of the measles virus, which affects humans, the Rinderpest virus that affects cattle, and the Phocine virus that causes seal distemper.

Canine influenza virus (CIV) is a recently emergent pathogen of dogs that has caused highly contagious respiratory disease in racing Greyhounds, pet dogs, and shelter animals.