Swine influenza (flu) is an infectious respiratory disease caused by type A influenza viruses that regularly cause outbreaks in pigs. Influenza is present at low levels in pigs throughout the world and is not a reportable disease in Canada.
Like human influenza viruses, there are different subtypes and strains of influenza viruses in pigs. The main influenza viruses circulating in pigs in recent years are H1N1, H1N2 and H3N2.
While influenza viruses mostly remain infectious within their host species, infections can sometimes spread to other species. Influenza viruses in pigs can occasionally infect people, and human influenza viruses can infect pigs.
Signs of swine influenza in pigs can include:
- loss of appetite
- weight loss
- coughing (barking)
- discharge from the nose or eyes
- difficulty breathing
- eye redness or inflammation and
- reduced fertility or abortion
Some pigs infected with influenza may not show any signs of illness.
Swine influenza is not a disease that transmits via food. As a result, there are no food safety concerns and pork continues to be safe to eat. As with any raw meat, pork should always be properly handled and cooked to eliminate a range of food safety concerns.
Producers should always follow strict biosecurity measures to reduce the risk of introducing infection to their animals, and notify a veterinarian if illness is suspected.
Information for producers and the livestock sector
Information for the general public
- Fact sheet – Swine flu virus: food safety facts for consumers
- Influenza (flu) in humans: symptoms and treatment
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