Standard pertussis vaccine immunity wanes substantially over time

The current vaccine for pertussis, or whooping cough, is highly effective at protecting people from the disease during the first three years after vaccination, but immunity wanes significantly over the subsequent four years, and there is little protection after seven years, found new research published in CMAJ (Canadian Medical Association Journal). “Despite waning immunity of the whooping cough vaccine, it’s important to note that the number of cases of pertussis in Canada is still quite low,” states Dr. Natasha Crowcroft, Public Health Ontario and the University of Toronto. “The most effective way parents can prevent whooping cough is to have their children immunized on time.” Before Canada’s public pertussis vaccine program, incidence of the disease averaged 156 cases per 100 000 people. In contrast, with a vaccination program, the number of new cases ranged from 2 per 100 000 in 2011 to 13.9 in 2012. Most cases are in under-immunized populations. The current...