Canine distemper virus is a highly infectious viral disease of dogs which can cause mild signs in some individuals, but may be fatal in others. Whilst vaccination has resulted in a decrease in the incidence of this disease in recent years, pockets of infection still exist, especially in large cities where there are many unvaccinated dogs. In other countries, like Finland, the disease is still a big killer of dogs.
Dogs less than one year of age are most commonly affected. However, those animals that have not been vaccinated or have weakened immune systems are also susceptible.
The main source of infection is by inhalation of aerosol droplets during close dog-to-dog contact. Signs can take up to three weeks to appear. The virus cannot survive easily in the environment and can be killed by most household disinfectants.
Canine distemper is a large virus related to the virus causing measles in man. It is a morbillivirus virus (this group of viruses also includes measles and seal distemper). Some strains of the virus may be more pathogenic than others. However, vaccination offers protection against all strains.
The early signs of disease are primarily respiratory with runny eyes and nose, and coughing. This is followed by depression, loss of appetite, vomiting and subsequently diarrhoea. In the later stages of the disease, dogs may develop thickening of the foot pads, known as ‘hard pad’, and nose. Dogs which survive may go on to show serious neurological signs including seizures (fits).
The vet will probably suspect that your dog might have distemper from the symptoms, the dog's vaccination history and the findings on physical examination. A blood test will also show a severe decrease in the white blood cell numbers and possibly the presence of virus bodies in the cells – this will help to confirm the diagnosis.
It is essential to vaccinate your dog according to your vet's recommendations. Pups that are born to vaccinated dams usually have antibodies from their mothers (maternal antibodies) that protect them against infection during the first few weeks of their lives. The pup is in danger after the level of maternal antibodies declines and that is when it should be vaccinated.
There is no specific treatment for canine distemper, although supportive
therapy in the form of intravenous fluids are often given to correct the
fluid loss due to vomiting and diarrhoea. The best form of protection against
this virus is through vaccination. You’ll be pleased to know that there are some vaccines that
offer a duration of immunity of three years, this means your dog is protected
for a full three years.