Dutch whooping cough epidemic puzzles scientists

Dutch scientists are struggling to identify the exact cause of an epidemic of whooping cough that has swept through the country despite vaccination rates as high as 96%. Similar problems are also being reported from Norway and Denmark.

The incidence of whooping cough in the Netherlands had been relatively low, but reported cases increased from 321 in 1995 to 2778 (18 per 100000 population) in 1996. By the end of November last year 3747 cases had been reported.

Reports have been widespread, with no clustering in areas of low vaccination. Neither has evidence been found for a similar increase in whooping cough in …