Is there some kind of difference between preventing an infectious disease and preventing infection from the bacteria that cause it? This FDA press release
http://www.fda.gov/…/newsr…/pressannouncements/ucm376937.htm
says that "acellular pertussis vaccines licensed by the FDA are effective in preventing the disease among those vaccinated, but . . . they may not prevent infection from the bacteria that causes whooping cough."
Is this some kind of word game or is there a real medical difference?