IOWA CITY, IA - AUGUST 11:  Marisa Grunder, 27 of Wilton, Iowa, is given a shot during trials of an H1N1 vaccine, developed by CSL of Australia, at University of Iowa Health Care, the University's medical center, on August 11, 2009 in Iowa City, Iowa.  The university's medical center is one of 8 trial sites across the nation conducting human studies on the new vaccine which is looking at optimal dosage levels for a variety of age groups. (Photo by David Greedy/Getty Images)