The virus is so widespread that President Barack Obama has declared a national emergency.
A new vaccine has been created to combat the virus, but there has been skepticism about its effectiveness, its danger and its administration.
CBS 60 Minutes correspondent Scott Pelley went inside the federal government's $3 billion H1N1 vaccine project to find out where and how the vaccine is made.
Here's a look:
More coverage of H1N1 Swine Flu on SmartPlanet:
- How much like the 1918 flu is H1N1?
- Time to put chemical vaccines into the H1N1 game?
- Paranoia is worse than swine flu
- Doubt break brings real response
- How many might the vaccine backlash kill?
- Video: Virus hunter aims to predict & prevent pandemics
- Could this swine flu be the vaccine?
- Was China right about swine flu?
- Business gets marching orders on swine flu
- Will a WHO panic stop the flu?