Publish Date: May 19, 2022
Influenza A virus (IAV) is a common cause of respiratory disease in swine. IAV infects pig populations across the globe, but vary by geographic region. Transmission between different animal species, including pigs and people, plays a major role in the rise of new IAV strains. Control of IAV in humans and swine is mutually beneficial and vaccines play a role in effective control programs.
Publish Date: June 3, 2006
The first descriptions of influenza in swine appeared in reports of a new disease affecting pigs on farms in western Illinois in 1918. The outbreaks occurred during the time of the great human influenza pandemic (“Spanish flu”) that was responsible for the death of over 20 million people worldwide. Because of the similarity in clinical signs to the disease in humans, the disease in swine was called “hog flu.” But another 12 years passed before researchers proved that the disease is caused by a virus in both swine and humans. The viruses responsible for illness in pigs and people were virtually indistinguishable, and these isolates served as the prototype classical Type A H1N1 influenza viruses. Most researchers believe that the virus, which originally existed in ducks, likely passed from the human to swine populations during the pandemic.