ATLANTA - MAY 05:  Acting CDC Director Richard Besser, M.D. (R) speaks Health and Human Services Secretary Kathleen Sebelius (L) listens during a press briefing at CDC headquarters May 5, 2009 in Atlanta, Georgia. They discussed develeopments in the H1N1 flu. Getty Images logo Getty Images 7 months ago

ATLANTA - MAY 05: Acting CDC Director Richard Besser, M.D. (R) speaks Health and Human Services Secretary Kathleen Sebelius (L) listens during a press briefing at CDC headquarters May 5, 2009 in Atlanta, Georgia. They discussed develeopments in the H1N1 flu.