Dozens of researchers, including myself, worked for years to uncover that swine flu had leapt to humans from a pig in Mexico in 2009. We learned a lot about influenza evolution, pig farming, and outbreak risk along the way.

The pathogen known as swine flu evolved in pigs in Mexico following imports of the livestock from the US and Europe.

Seven years of surveillance and research revealed the complex history of the H1N1 virus that leapt from pigs to humans and sparked the global swine flu outbreak.

Dozens of researchers, including myself, worked for years to uncover that swine flu had leapt to humans from a pig in Mexico in 2009. We learned a lot about influenza evolution, pig farming, and outbreak risk along the way.