Origin of the 2009 H1N1 Flu Pandemic: A Timeline

Mexico

The 2009 flu pandemic, also known as the swine flu pandemic and sometimes called the H1N1 flu, was caused by a new strain of H1N1 influenza A virus that emerged in Mexico in March 2009. The virus was first detected in two children from the same family in the La Gloria community of Perote, Veracruz, Mexico. The children had mild respiratory illnesses and recovered quickly. The virus was then detected in other parts of Mexico and soon spread to the United States and other countries.