Researchers: Whooping cough vaccine fades after 3 years

A small study finds that protection from the whooping cough vaccine last only three years, supporting health mandates that call for regular booster shots for children. The short-term protection could explain the recent rash of pertussis cases.

Dr. David Witt, chief of infectious disease at the Kaiser Permanente Medical Center in San Rafael, CA, examined whooping cough cases in California's Marin County. Witt and his team found the disease was most common in vaccinated kids ages 8 to 12, leading the researcher to conclude the effectiveness of booster shots given to those children when they were younger faded within three years.

The findings were surprising because the team expected the highest infection rates to be in children who weren't vaccinated against pertussis. "I was disturbed to find maybe we had a little more confidence in the vaccine than it might deserve," noted Witt, according to the Washington Post.

Other medical experts warn against drawing too many conclusions from Witt's research until further studies are conducted. The CDC didn't comment on the study, but it did tell MedPage Today it has observed a drop-off in the vaccine's protection after 5 years. It will further study the data at a meeting next month.

- read the Washington Post article
- get more from MedPage Today