Study: Vaccine for whooping cough fades

Associated Press

ATLANTA

The whooping-cough vaccine given to babies and toddlers loses much of its effectiveness after just three years — a lot faster than doctors believed — and that could help explain a recent series of outbreaks in the U.S. among children who were fully vaccinated, a study suggests.

The study is small and preliminary, and its authors said the results need to be confirmed through more research.

“I was disturbed to find maybe we had a little more confidence in the vaccine than it might deserve,” said the lead researcher, Dr. David Witt, chief of infectious disease at the Kaiser Permanente Medical Center in San Rafael, Calif. Witt presented his findings Monday at the American Society for Microbiology conference in Chicago.