Five canines in Canada who came into contact with two other dogs from South Korea are now infected with a strain of canine influenza and have tested positive for the highly contagious disease in southwestern Ontario.

The infection was passed on by two dogs imported from South Korea in a foster home with other dogs from Windsor-Essex animals. The health unit is working to ensure the flu does not spread beyond the foster home.

Canine influenza is a highly contagious viral infection affecting dogs mostly, but also the occasional cat. It is particularly infectious in Canada, where the animals do not have natural immunity from a previous infection and canine influenza vaccination is rare.

Distinguishing the canine flu is difficult in dogs because the symptoms are similar to other respiratory infections like Kennel Cough. It gives them a fever, they feel pretty run down, and they get a cough which is often the most distinguishable sign. It usually runs its course but, like the flu, it could cause complications for older dogs or canines with existing health problems.


Signs of Canine Influenza

Almost all dogs exposed to canine H3N2 influenza virus become infected, with approximately 80% developing clinical signs of disease. The approximately 20% of infected dogs that do not exhibit clinical signs of disease can still shed the virus and spread the infection.

Like other mammalian influenza viruses, canine influenza virus causes an acute respiratory infection in dogs. There is no season for canine influenza, and infections can occur any time of the year. Canine influenza virus infection often resembles Kennel Cough, which is caused by one or more bacterial or viral infections.

Some dogs are more severely affected and exhibit clinical signs of pneumonia, such as a high-grade fever and increased respiratory rate and effort. Chest x-rays may reveal consolidation of lung lobes. Although most dogs recover without incident, deaths due to canine influenza have been reported.

Cats infected with H3N2 display signs of upper respiratory disease, including nasal discharge, congestion, malaise, lip-smacking and excessive salivation.



Veterinary expertise is required to determine treatment options and the best course of treatment. Treatment for canine influenza, as for most viral diseases, is largely supportive. Good nutrition may help dogs mount an effective immune response. Most dogs recover from canine influenza within 2 to 3 weeks.

Treatment modifications should be made as needed, based on response to treatment, other health factors, and other factors such as compliance and animal care capabilities of the owner.

To prevent transmission of the virus, dogs infected with canine H3N2 influenza as well as other dogs in the household should be isolated for 4 weeks.


Who should be vaccinated?

  • Dogs that will be travelling to areas where there is canine flu activity
  • Dogs that may have contact with dogs imported from Asia. This includes mainly dogs in rescues and kennels that are actively importing dogs, as well as dogs in households of people thinking about adopting a dog from Asia.


When else might vaccination be useful?

The benefits of vaccination decrease as the likelihood of exposure decreases. There are a few more groups where vaccination could be considered:

  • Dogs at increased risk of exposure. This includes dogs that have frequent contact with lots of other dogs, especially dogs from a wide geographic range, such as those that travel for shows or other similar events.
  • Dogs at increased risk of serious consequences. This includes dogs with pre-existing heart disease or lung disease, and senior dogs,

Canine flu could pop up in any given city tomorrow, but it also might not happen for years. At the moment, it’s hard to say that vaccination is broadly indicated in Canadian dogs, but if people are particularly worried about flu, it’s a safe vaccine and there’s no reason not to get it.

If you suspect your dog or cat has come down with Canine flu or Kennel Cough give us a call by clicking on the link HERE