Distemper, also called hardpad disease, is a contagious disease caused by a virus. This disease, which is often fatal in wild animals, is very common in Québec. It mainly affects canids, as well as raccoons and skunks, but is not transmissible to humans.

Vigilance is necessary because the signs of distemper resemble those of rabies, the latter being lethal and transmissible to humans.

Animals at risk

In Québec, distemper particularly affects raccoons and skunks. This disease is also present in many carnivores, namely in:

  • Canidae such as dogs, wolves, coyotes and foxes;
  • Mustelidae such as minks, martens and ferrets;
  • Ursidae such as black and polar bears;
  • Felidae such as lynx and big cats, but not domestic cats.

Signs of the disease in animals

The signs associated with the disease vary greatly depending on the species and the animal’s immune response. The distemper-infected animal may have several of these symptoms: 

  • passivity;
  • circling or aimless wandering behaviours;
  • nervous problems (e.g., partial paralysis, poor movement coordination, salivation, convulsions, chewing-gum fits);
  • behavioural changes (e.g., loss of human fear or atypical aggression in wildlife);
  • conjunctivitis;
  • nasal discharge and respiratory problems (e.g., pneumonia);
  • skin problems (pustules, hyperkeratosis of plantar pads, palm pads and/or nose);
  • digestive problems (vomiting, diarrhea with blood, often associated with rapid dehydration);
  • dental and testicular lesions.

Between 25% and 75% of dogs show no signs of disease. The others may show one or more of the signs described. Nasal and eye discharge with conjunctivitis is usually the first sign illness in dogs. Up to half of infected dogs, especially those with nervous signs, will die. Because the virus weakens the immune system, other infections can develop.

Transmission and incubation period

Distemper is a highly contagious disease. It is mainly transmitted by aerosols (airborne microdroplets) or by direct and indirect contact with oral, respiratory and ocular fluids (e.g., saliva, sneezing), urine or feces of infected animals.

An animal can be contagious even if it shows no signs of disease. The virus can be transmitted for more than 90 days after infection.

The dog may be contagious one week after contamination and up to four months after the disease.

The distemper virus is relatively fragile and rapidly destroyed in the environment by ultraviolet rays, heat and drought. However, because it is very cold-resistant, it can be contagious in the environment at a temperature of 4°C for several weeks.

Time between the entry of the virus into the animal’s body and the onset of the disease

The incubation time for this disease is one to six weeks. The symptoms last one to six weeks.


There is no specific or highly effective treatment for animals showing signs of distemper. A veterinarian may propose a support treatment. Many unvaccinated animals will die or maintain permanent consequences from the infection.

Protection and prevention

It is recommended that dogs and ferrets be vaccinated against this disease.

Distemper is not recognized as a disease transmissible to humans. However, the resemblance between the signs of distemper and rabies, which is a serious disease that is transmissible to humans, requires adopting safe habits when faced with an animal presenting such signs.

Any wild animal with abnormal appearance or behaviour (e.g., atypical aggression, loss of human fear, disorientation, confusion) should be reported.

If you have been bitten or scratched by an animal or have come into contact with its saliva, refer to the Preventive measures after coming into contact with a potentially infected animal section and promptly contact Info-Santé 811.

If your animal has been bitten or scratched by another animal or has been in contact with its saliva, immediately apply protective and preventive measures and contact your veterinarian.

The distemper virus can be destroyed by heat and disinfectants. A solution consisting of one part of bleach diluted in nine parts of water will be effective. It is recommended to safely dispose of carcasses of animals suspected of having distemper to limit the potential exposure of other animals that may develop distemper.

Last update: January 8, 2024


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