Colds and flu

Updated 27 September 2017

2009 swine flu originated in Mexico

Genetic analysis has pinpointed the source of the pandemic influenza that killed 17,000 people worldwide.

The 2009 swine flu pandemic originated in pigs in a small region of central Mexico, a new study reports.

'Jumped' into humans

Researchers used genetic analysis to pinpoint the source of the H1N1 pandemic. This version of the swine flu killed more than 17,000 people worldwide. The scientists used the same type of genetic analysis to learn how the virus jumped from pigs to people.

It's the first time the origin of a pandemic flu virus has been determined in such detail, the study authors said.

Read: Swine flu fact file

The virus was a combination of a North American swine virus that had jumped between birds, humans and pigs, and a Eurasian swine virus that circulated for more than 10 years in pigs in Mexico before jumping into humans, the investigators said.

"Knowing where and how an animal influenza virus infects humans and spreads all over the world helps us understand how we can reduce risk of these pandemics," said study senior author Adolfo Garcia-Sastre.

Read: If you had flu, it most likely was swine flu

He is director of the Global Health and Emerging Pathogens Institute at the Icahn School of Medicine at Mount Sinai in New York City.

"This virus came from, and was confined to, a very small geographic area, and had been there 10 years before one emergent strain gained the capacity to infect humans. The virus was completely under the radar," he explained in a hospital news release.

The study was published online in the journal eLife.

Read more:

Symptoms of flu

Causes of flu

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Dr Heidi van Deventer completed her MBChB (Bachelor of Medicine and Bachelor of Surgery) degree in 2004 at the University of Stellenbosch.
She has additional training in ACLS (Advanced Cardiac Life Support) and PALS (Paediatric Advanced Life Support) as well as biostatistics and epidemiology.

Dr Van Deventer is currently working as a researcher at the Desmond Tutu Tuberculosis Centre at the University of Stellenbosch.

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