(CNN)Here's a look at the H1N1 influenza virus, also known as swine flu. There was a pandemic outbreak across the globe which lasted from 2009 to 2010.
Human cases of H1N1 from April 2009-April 2010
Fatalities in the United States - Estimated total is 12,469.
Fatalities Worldwide - A 2012 study estimated a range between 151,700 and 575,400 deaths.