Key Facts about Canine Influenza (Dog Flu)

What is canine influenza (dog flu)?

Canine influenza (also known as dog flu) is a contagious respiratory disease in dogs caused by specific Type A influenza viruses known to infect dogs. These are called “canine influenza viruses.” No human infections with canine influenza have ever been reported. There are two different influenza A dog flu viruses: one is an H3N8 virus and the other is an H3N2 virus. Canine influenza A(H3N2) viruses are different from seasonal influenza A(H3N2) viruses that spread annually in people.

Can canine influenza viruses infect people?

In general, canine influenza viruses are thought to pose a low threat to people. To date, there is no evidence of spread of canine influenza viruses from dogs to people and there has not been a single reported case of human infection with a canine influenza virus in the U.S. or worldwide. In 2016, CDC used the Influenza Risk Assessment Tool to evaluate the potential pandemic risk of canine influenza H3N2 viruses and found it to be low.

However, influenza viruses are constantly changing and it is possible that a canine influenza virus could change so that it could infect people and spread easily between people. Human infections with novel (new, non-human) influenza A viruses against which the human population has little immunity are concerning when they occur because of the potential that a pandemic could result. For this reason, the World Health Organization global surveillance system has led to detection of human infections by novel influenza A viruses of animal-origin (such as avian or swine influenza A viruses), but to date, no human infections with canine influenza A viruses have been identified.

https://www.cdc.gov/flu/other/canine-flu/keyfacts.html