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Influenza A viruses are found in many different animals, including ducks, chickens, pigs, whales, horses, seals, and cats.
Avian influenza refers to the disease caused by infection with avian (bird) influenza viruses.
Swine influenza is a respiratory disease of pigs caused by type A influenza viruses that regularly cause outbreaks of influenza in pigs.
Influenza viruses that normally circulate in pigs are called “variant” viruses when they are found in people.
An influenza pandemic can occur when a non-human (novel) influenza virus gains the ability for efficient and sustained human-to-human transmission and then spreads globally.
Information about actions, apart from getting vaccinated or taking medicine, that people and communities can take to help slow the spread of illnesses like influenza (flu). NPIs are also known as community mitigation strategies.