Swine Influenza (Influenza in Swine)
Swine Influenza (swine flu) is a respiratory disease of pigs caused by type A influenza virus that regularly causes outbreaks of influenza in pigs. Swine flu viruses can cause high levels of illness in pig herds, but cause few deaths in pigs. Swine influenza viruses can circulate among swine throughout the year, but most outbreaks occur during the late fall and winter months similar to outbreaks of seasonal influenza in humans. The main swine flu viruses circulating in U.S. pigs in recent years are: swine triple reassortant (tr) H1N1, trH3N2 and trH1N2. With the exception of the 2009 H1N1 virus, influenza viruses that circulate in swine are very different from influenza viruses that commonly circulate in people.
More information about swine influenza in swine is available at the following links:
- USDA Swine Influenza Surveillance
- Key Facts about Swine Influenza (Swine Flu) in Pigs
- What People Who Raise Pigs Need To Know About Influenza (Flu)
Information about swine influenza in humans (called variant viruses) is available at Variant Influenza Viruses in Humans.
- Page last reviewed: August 20, 2012
- Page last updated: August 20, 2012
- Content source:
- Centers for Disease Control and Prevention, National Center for Immunization and Respiratory Diseases (NCIRD)
- Page maintained by: Office of the Associate Director for Communication, Digital Media Branch, Division of Public Affairs