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 adenovirus type 2 (CAV2) causes respiratory disease in dogs and is one of the infectious agents commonly associated with canine infectious tracheobronchitis, which is also known as “kennel cough”. Canine infectious tracheobronchitis is usually spread through coughing. Dogs that are around other dogs, such as at boarding facilities and dog parks, are at increased risk for infection.