Influenza A viruses have infected many different animals, including:
- Ducks
- Chickens
- Pigs
- Whales
- Horses
- Seals.
However, certain subtypes of influenza A virus are specific to certain species, except for birds, which are hosts to all known subtypes of influenza A. Influenza A viruses normally seen in one species sometimes can cross over and cause illness in another species. Most recently, this occurred when H3N8 viruses from horses crossed over and caused outbreaks in canines. This is known as canine flu or dog flu.
Initially, the canine
flu virus was identified in racing greyhounds, and there was some speculation that the virus was exclusively causing disease in this breed. However, canine flu has now been confirmed in the domestic canine population in general, first in the state of Florida, and then in other states. There has never been a documented case of human infection with this virus.
Dogs can become infected with the canine flu virus and show no canine
flu symptoms. In other cases of the canine flu, symptoms can be severe. The canine flu virus can cause a respiratory disease that mimics a syndrome called kennel cough.
Common symptoms of canine flu include:
- Cough
- Nasal discharge
- Fever.