H3N2 Canine Influenza Outbreak

The following are some common questions and answers about the H3N2 canine influenza outbreak that’s ongoing in the US.

How far will it spread?

Who knows? It’s always hard to predict what will happen with influenza viruses. The spread of the H3N8 canine flu virus was surprisingly slow and sporadic, and it has yet to establish itself in Canada. This new H3N2 strain concerns me more because it might be more transmissible, and the Midwest US outbreak is unlike what we’ve seen in the past with H3N8. I suspect it will continue to spread, at least for a while.

How do we contain it?

Basic infection control measures.

Which are?

  • If your dog is sick, keep it away from other dogs. Influenza viruses are only shed for a short period of time, so keeping sick dogs away from other dogs for 7-14 days will help.
  • If your dog has been exposed to dogs that might have been infected, keep it away from other dogs. It doesn’t matter if your dog is healthy. Peak flu shedding can occur very early in disease, and a lot of virus can be shed in the 24 hours before the dog starts to show signs of illness. So, keeping exposed animals away from others for 7-14 days after exposure is also a good idea, just in case.
  • Don’t travel to an endemic region with your dog. If you are going on a trip to Chicago or other area where H3N2 is active and you don’t need to bring your dog along, then don’t risk exposing your dog, and/or possibly bringing the virus home with it.
  • Don’t travel out of an endemic region with your dog. Likewise, if you live in an area where H3N2 is active, don’t take your dog on a trip anywhere else. If it was infected before leaving, it could take the virus to a new region.
  • Don’t import dogs from shelters, puppy mills or similar facilities in areas where H3N2 is active. Animals from these facilities are at higher risk for carrying many diseases, now including canine flu.
  • If the virus is active in your area, decrease dog-dog contact. Staying away from places where lots of dogs congregate (e.g. dog parks) can reduce the risk of exposure.
  • If you think your dog might have canine flu, don’t rush it to your vet. It might need to go to the vet, but that depends on severity of disease. Regardless, the best approach is to call first and mention the potential for influenza so that the vet clinic can take precautions (more on that coming soon in another post).

Does this virus pose a risk to people?

Probably not (or very limited), but flu viruses like to change. So, using basic infection control practices around infected dogs makes sense. It’s also important that situations in which people and dogs in the same household have respiratory disease be investigated to make sure that there hasn’t been interspecies flu virus transmission.