Canine influenza is a viral respiratory infection in dogs. There are two strains identified in the United States: H3N8 and H3N2. Occasionally dogs can be infected with the circulating human influenza virus. Outbreaks among dogs have been reported in Florida (2004) and Illinois (2015). Recently, H3N2 has been reported in Washington State. As of this newsletter, there have been no cases of H3N2 reported in Oregon.
Signs of illness can vary greatly, but usually dogs will have a cough, runny nose and sometimes a fever. Canine influenza virus is very contagious and most dogs become sick within 24 hours of exposure. Canine influenza is an airborne disease, much like kennel cough, so the virus is spread through droplets from a cough or sneeze or by coming in contact with contaminated objects (i.e. toys). Most infected dogs are mildly ill and recover completely with supportive care. In rare cases, canine influenza infection can lead to pneumonia or other bacterial infections and require antibiotics.
Infection risk is much higher in dogs who attend daycare, training classes, dog parks or boarding facilities. After the 2004 H3N8 outbreak, a vaccine was developed, but similar to the human influenza vaccine, cross protection between strains is unlikely. A H3N2 vaccine has been conditionally released in December of 2015, but is still pending large efficacy and safety studies. Most Oregon dogs do not need the vaccine, but if you have concerns or questions about your dog’s canine influenza infection risk, please contact us.