Canine Flu Update

There has been recent concern about whether the canine flu is a problem in the Northwest.  We discuss this issue frequently during appointments.  At this time, it doesn’t appear to be a major threat. 

Canine influenza viruses (CIV H3N8 and CIV H3N2) cause a respiratory infection in dogs that is often referred to as 'Canine Flu'. Canine influenza virus (CIV) is one of the causes of CIRDC (Canine Infectious Respiratory Disease Complex) - also called “Canine Cough” or “Kennel Cough”.  The clinical signs of CIRDC include coughing, sneezing, nasal discharge, eye discharge and fever.  Pneumonia may occur as a complication.   


Influenza A, or Canine Influenza Virus (CIV H3N8), was first identified in racing greyhounds in Florida in 2004.  Genetic analysis shows that the original canine influenza virus is closely related to equine influenza virus, suggesting that it evolved from equine influenza virus and jumped species.  The virus has a high rate of causing sickness but a low rate of serious complications.  It is passed directly, aerosolized and can be transmitted on inanimate objects (fomites).  It is easily killed with bleach and other disinfectants and is not known to infect people.  Virtually all dogs are susceptible.  The disease is more likely in populations such as animal shelters, boarding facilities, dog parks, dog shows, or day care settings.

CIV H3N2 emerged in the Chicago outbreak of 2015. This virus is of avian origin and not related to the earlier CIV H3N8 virus.  Recently, two dogs associated with a respiratory illness outbreak in a King County boarding and dog daycare facility had laboratory results indicating H3N2 positive infection through PCR testing.  Since that time, no other cases have been reported and we have not experienced a rise in kennel cough cases.  We did recently test a patient at Lien Animal Clinic suspected to have influenza but the test came back negative.

We do have H3N2 influenza vaccine for use in high risk dogs who frequent shelters, boarding facilities, dog parks, or dog shows. We have not been recommending it routinely.  This certainly may change if more cases emerge.

For more information and ongoing updates, visit the Seattle and King County public health website.