Basic Information on the Outbreaks

•  Both flus stemmed from animal vectors—pigs in the case of swine flu ¹ and birds in the case of avian flu ².
• Both have surfaced before in history, with avian flu appearing most recently in both 1997 and 2003 ³ and a genetically similar form of swine flu appearing in the 1918 pandemic ⁴
• Avian flu is primarily found in birds such as chickens and migratory birds, but the 2005 strain “appeared to mix with human flu viruses without an intermediate host, such as pigs,” which is normally how viruses cross species ⁵
• Swine flu arose from “pigs in Asia” before travelling around the world in humans, “contrary to the popular assumption that the new swine flu pandemic arose on factory farms in Mexico” ¹. This strain was “relatively new” in the combination of its genes, which meant “few people had full resistance to it” ⁷
• Avian flu remained fairly isolated in specific counties in East and Southeast Asia ⁸ Swine flu “crossed borders and oceans” to over 74 countries by the end of the outbreak ⁴
• Swine flu is estimated to have killed around 12,000 people from the flu itself or related complications ¹⁰
• The “CDC estimates that 43 million to 89 million people H1N1” ¹¹
• The majority who died in both outbreaks were under 65, the normal age of those affected by seasonal flu ¹⁰
• There have been only 649 cases of confirmed avian flu since December 2003 with 385 deaths ¹³

Depiction of swine flu confirmed cases in early stages of the pandemic

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