Thomas Clark, chief of the meningitis branch of the U.S. Centers for Disease Control and Prevention, listens to a question at Princeton University in Princeton, N.J., Monday, Dec. 9, 2013. Clark was ... more 
Thomas Clark, chief of the meningitis branch of the U.S. Centers for Disease Control and Prevention, listens to a question at Princeton University in Princeton, N.J., Monday, Dec. 9, 2013. Clark was on campus to oversee the vaccinations of nearly 6,000 students in an attempt to stop an outbreak of type B meningitis. (AP Photo/Mel Evans) less 
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Associated Press | Photo By Mel Evans
Mon, Dec 9, 2013 6:20 PM EST