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Background Information on Influenza in Pigs
NOTE: This page contains background information about influenza in pigs. This page does NOT contain information about novel H1N1 influenza (initially referred to as swine flu when it was first detected) that is spreading from person to person around the world. For information about novel H1N1 influenza, see the CDC Novel H1N1 Flu website.
Influenza A viruses are found in many different animals, including ducks, chickens, pigs, whales, horses and seals. Pigs can be infected with both human and avian influenza viruses in addition to swine influenza viruses. Infected pigs get symptoms similar to humans, such as cough, fever and runny nose. Because pigs are susceptible to avian, human and swine influenza viruses, they potentially may be infected with influenza viruses from different species (e.g., ducks and humans) at the same time. If this happens, it is possible for the genes of these viruses to mix and create a new virus. This type of major change in the influenza A viruses is known as antigenic shift. Antigenic shift results when a new influenza A subtype to which most people have little or no immune protection infects humans. If this new virus causes illness in people and can be transmitted easily from person to person, an influenza pandemic can occur.
- Key Facts about Influenza in Pigs
How does flu in pigs spread? Can people catch influenza from eating pork? - What pork producers need to know about swine influenza (flu) in pigs and people
NOTE: This brochure is currently being updated, and a new brochure related to novel H1N1 influenza in people is under development and will be posted shortly. - Interim Guidance for People who have Close Contact with Pigs in Non-commercial Settings
See also General Information on Novel H1N1 Flu.
- Page last updated June 15, 2009
- Content Source: Coordinating Center for Infectious Diseases (CCID)
- National Center for Immunization and Respiratory Diseases (NCIRD)
