Illustration of a targeted virus over a world map
The Hunt for a Pandemic’s Origins
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 Hunt for a Pandemic’s Origins
The Hunt for a Pandemic’s Origins

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.

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.

ABOVE: © istock.com, bgblue
virus hybrid
Illustration of a world map showing a truck going from the US to Mexico, a plane going from Europe to Mexico, and a pig surrounded by various viruses in Mexico
Infographic: How H1N1 Came to Spark a Pandemic in 2009
Martha Nelson | Jan 4, 2022
The pathogen known as swine flu evolved in pigs in Mexico following imports of the livestock from the US and Europe.
An illustration with a world map, pigs, and viruses
Timeline: Investigating the Origins of the 2009 Pandemic
Martha Nelson | Jan 4, 2022
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.
RNA-DNA Virus Hybrid Found
Sabrina Richards | Apr 20, 2012
Researchers discovered a virus produced from recombination between RNA and DNA viruses, suggesting a possible new mechanism of virus evolution.