Canine distemper is a highly contagious viral disease that affects domestic dogs and other animals such as ferrets, skunks, raccoons, and foxes. It is caused by the canine distemper virus (CDV) and is spread mainly by direct contact between a susceptible dog and an infected dog showing symptoms. Coughing and sneezing can also spread the virus over short distances.

The symptoms of canine distemper can take up to 14 days to show up after exposure and can affect the respiratory, gastrointestinal, skin, immune, and central nervous systems. The symptoms include fever, nasal discharge, eye discharge, lethargy, sneezing, coughing, difficulty breathing, vomiting, diarrhea, loss of appetite, thickening of nose and foot pads, pneumonia, skin sores, and pain.

There is no cure for canine distemper infection, and treatment typically consists of supportive care and efforts to prevent secondary infections, control vomiting, diarrhea, and neurologic symptoms, and combat dehydration through administration of fluids. Dogs infected with canine distemper must be separated from other dogs to minimize the risk of further infection.

Vaccination is crucial in preventing canine distemper, and a series of vaccinations is administered to puppies to increase the likelihood of building immunity when the immune system has not yet fully matured. After the initial puppy vaccine boosters, additional distemper boosters should be given to adult dogs every one or three years, depending on which vaccine is used.