[Silver Spring, October 14. Image via Getty]

County healthcare workers make announcements to residents waiting in a long line for the H1N1 vaccination shot at a clinic held by the Montgomery County Health and Human Services on October 14, 2009 at the Dennis Avenue County Health Center in Silver Spring, Maryland. Swine flu is killing fewer people than seasonal flu but is causing greater alarm due to its impact on children and higher healthcare costs, according to a top disease surveillance expert. Denis Coulombier, who heads the European Centre for Disease Prevention and Control's preparedness and response unit, warned that a second wave of swine flu infections could be expected within weeks. AFP PHOTO / Tim Sloan (Photo credit should read TIM SLOAN/AFP/Getty Images)