Canine distemper
Also called Hardpad disease
A serious viral disease of dogs that affects the breathing, gut and nervous system. It starts like a cold and can end in seizures, muscle twitching and paralysis.
Cause and spread
- Cause
- Canine distemper virus, a paramyxovirus related to the measles virus.
- How it spreads
- Mainly through droplets in the air from infected dogs. Some dogs shed the virus for months. The virus also affects ferrets, mink and wild carnivores.
Signs to watch for
- Fever, which may return after a few days
- Eye and nose discharge, cough and pneumonia
- Vomiting and diarrhoea
- Thickened, hard footpads and nose in some dogs
- Muscle twitching, seizures and unsteady walking, which may come weeks later
- Weak immunity and secondary infections
Many diseases look alike. Only a laboratory test can tell them apart, so please see a veterinarian for any sick animal.
How it is diagnosed
Diagnosis starts with the signs and vaccination history, and is confirmed by RT-PCR to find the virus or by antibody tests. Unvaccinated dogs with fever and breathing, gut or nerve signs are suspected first.
Prevention and control
- Vaccinate: distemper is a core vaccine, given from 6 weeks of age at intervals until 16 weeks, as advised by your veterinarian
- Keep unvaccinated puppies away from sick dogs
- Isolate suspected cases
Where this information comes from
- Canine Distemper · Merck Veterinary Manual
General information for animal owners and veterinarians, last checked October 2026. It does not replace the advice of your veterinarian, who should decide which tests and treatment your animal needs.