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 IR£2.75 million in damages to the family of Kenneth Best who, in 1969, suffered severe brain damage after being vaccinated.