see more

A hospital employee exits the ready room to be used for possible swine flu patients April 30, 2009 at the Washington Hospital Center in Washington, DC. The room provides extra capacity for mass casualty incidents and can be used as a pre-screening and treatment area for patients who require special isolation. AFP PHOTO/Mandel NGAN (Photo credit should read MANDEL NGAN/AFP via Getty Images)

A hospital employee exits the ready room to be used for possible swine flu patients April 30, 2009 at the Washington Hospital Center in Washington, DC. The room provides extra capacity for mass casualty incidents and can be used as a pre-screening and treatment area for patients who require special isolation. AFP PHOTO/Mandel NGAN (Photo credit should read MANDEL NGAN/AFP via Getty Images)