Pertussis vaccine offers good protection to babies but wanes in a few years: study
TORONTO — The current vaccine for pertussis, or whooping cough, is highly effective during the first three years after children get their shots, but immunity wanes over the next several years, leaving little protection from the disease, researchers say.
In an Ontario study published Monday in the Canadian Medical Association Journal, researchers found that immunity begins waning about four years following the last scheduled childhood immunization or booster shot given to an adolescent or adult. Within a few more years, the vaccine’s effectiveness has diminished significantly.
“The protection that the vaccine gives is very good in the first couple of years after the immunization is given,” said Dr. Natasha Crowcroft, chief of applied immunization research for Public Health Ontario. “So it’s good news for protecting babies.
“But that protection, it fades pretty quickly. So by the time you’re at seven or eight years (out), you’ve got very little protection left.”