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Canine Influenza Information Page

Canine Influenza has been in the news quite a bit recently and for good reason; below we offer information to help you make the best decision for your dogs health regarding this virus.


The canine influenza virus (CIV) is a viral respiratory infection found primarily in dogs but which can also affect cats. There have been two identified strains of the virus in the US: H3N8 and H3N2. These viruses are considered to be prevalent in the United States.


The first evidence of H3N8 canine influenza in companion dogs was documented in spring 2005. It is believed to have jumped species from horses and was first identified in an outbreak of respiratory illness in racing dogs in Florida in 2004. H3N8 does not affect cats.


In 2015, a canine influenza outbreak in the Midwest was determined to have been caused by the H3N2 subtype, which had been circulating in Asian dogs since 2007. This month there was an outbreak of H3N2 CIV in the South Bay area of California. This virus appears to spread faster, shed longer, and have the potential to be more serious than the H3N8 strain. To date there have been no positive cases in Oregon (January 2018).


Canine influenza is an airborne disease; much like kennel cough (Bordetella bronchiseptica). The virus can travel in droplets from a cough or sneeze and can be transmitted by contact with contaminated objects (for instance, a chew toy). The most common clinical signs are;

  • Coughing.
  • Loss of appetite.
  • Lethargy.
  • Fever.
  • Sneezing.
  • Discharge from the eyes and/or nose.

Dogs can become ill within 24 hours of exposure. Some dogs don’t show symptoms, but are able to infect other dogs for weeks. Most dogs diagnosed with canine influenza experience a mild form of the disease. Unfortunately, dogs in the US have no immunity to influenza, and therefore nearly all exposed dogs will become infected.

Cats can potentially get this from dogs but transmission is low- there is no vaccine for cats so we would only suggest people separate sick dogs from cats.


Practically speaking, if your dog stays at home and rarely contacts other dogs, its risk of contracting the virus is likely low. If your dog is boarded, goes to day care, or the dog park, it may be at a higher risk.

If your dog is coughing, it should not go to public places where it could contact other dogs until your veterinarian agrees it’s safe for your dog to go out.

Call us if your dog develops a cough, especially if it has already received the Bordetella vaccine. If your dog is coughing, do not take it out to locations where it may infect other dogs, including grooming or boarding environments. Early intervention is key to limiting community outbreaks.

Be sure to let us know if your dog has been boarded, visited the groomer or was involved in any social activities (dog park, day care, etc.) within the last month.


We treat every patient as an individual and we take multiple factors into consideration when we partner with you to make these types of decisions. Some factors we will discuss include; over-all health status, exposure to other dogs, and even your own risk tolerance. We will begin carrying vaccine for BOTH strains to ensure best coverage in any and all lifestyle situations.

The vaccine is two doses about three weeks apart.

Dogs will NOT be protected until 10-14 days after their 2nd booster, so you will want to plan ahead if you will be traveling to an area of possible exposure.

  • This vaccine needs to be boostered yearly.
  • Side effects, if any, tend to be soreness and lethargy.
  • No vaccine is 100% effective but vaccinated dogs tend to have milder clinical signs.

>>> Cornell University Canine Influenza Tracking Map

As always, we are here for any questions or concerns you may have and we are honored to be part of your pet’s health care team.