November 13, 2019 Dogs

Canine Flu Facts 2019

Two veterinary professionals examine a white dog on an exam table

Canine Flu Facts 2019

Anyone listening to the news these days knows it’s the start of flu season for humans. While human influenza viruses circulate year-round, cases of the flu start increasing in November, peak in December and January and peter out by spring. Dogs have their own species-specific flu viruses, but canine flu viruses circulate year round rather than during the fall and winter. This blog post will highlight some of the differences between flu in dogs and their humans.

Flu Virus ABCs (…and D)

All influenza viruses, whether they infect people or animals, fall into one of four types, creatively named A, B, C and D. When we get our annual flu vaccine, it typically has both A and B type viruses, although the exact mixture varies from year to year. All three known canine influenza viruses belong to the Type A group.

Dog Flu 1-2-3

Influenza in dogs is what healthcare professionals call an emerging disease. The first reports of a canine-specific influenza virus occurred just 15 years ago, in 2004. Currently, there are three identified strains of canine flu virus. The H3N8 virus originally infected horses, but mutations resulted in the virus gaining the ability to spread from dog to dog. In 2007, a second canine influenza virus, H3N2, arose in South Korea. This virus was originally an avian influenza virus. In 2015, it spread to the United States, appearing in Chicago during a canine respiratory disease outbreak. This virus is the most commonly diagnosed canine influenza today. The third strain of canine influenza, H5N2, is the newest canine influenza virus. Isolated in China in 2009, this virus has not yet made its way to the United States.

Dog Flu Happens Everywhere

Dog owners should be keen to know where canine influenza occurs so they can discuss a preventive care plan with their veterinarian. Like human influenza, canine influenza happens pretty much everywhere. And like human influenza, canine influenza shows up in population-dense areas first. Knowing that information, you should not be surprised to learn that canine influenza has been reported in 46 of the 48 continental states. Only two states, North Dakota and Nebraska, have not reported cases.

An Ounce of Prevention

A vaccine against the H3N8 and H3N2 strains of canine influenza is available for dogs. Veterinarians specializing in infectious disease categorize flu vaccines as “non-core,” meaning they are only necessary for at-risk dogs (as opposed to “core” vaccines that are required for every dog). Since canine influenza spreads from a sick dog to a susceptible dog, dogs in frequent contact with other dogs in boarding kennels, at doggie daycare, agility or confirmation competitions are considered to be at-risk. If your dog may be at-risk, ask your veterinarian if the flu vaccine is right for your dog.

More Flu Facts

Now that you have your dog’s flu prevention plan in place, check out the Centers for Disease Control’s recommendations for flu prevention in humans. Cats can get the flu too. Read a prior blog post to learn more.