A Finnish study found that in a population with a 98 per cent immunisation rate, whooping cough infections remain common.
Swabs were taken from 584 patients with a cough at 32 health centres. The study found that B pertussis and parapertussis (which both cause whooping cough) were equally common in pre schoolchildren, but that the incidence of B pertussis (which cause a more virulent form of the disease than B parapertussis) was higher in school children and adults. This suggests that protection from the vaccination decreases over time (JAMA, 1998; 280: 635-7).
In Ireland, health boards are reviewing their records to find out how many babies may have received a toxic dose of the pertussis vaccine in 1968. This comes after the Irish Supreme Court ordered Wellcome to pay IRlb2.75 million in damages to the family of Kenneth Best who, in 1969, suffered severe brain damage after being vaccinated.