Pertussis Outbreak in the Netherlands Despite High Vaccination Rates
Author Information
Author(s): H.E. de Melker, M.A.E. Conyn-van Spaendonck, H.C. Rumke, J.K. van Wijngaarden, F.R. Mooi, J.F.P. Schellekens
Primary Institution: National Institute of Public Health and the Environment
Hypothesis
What caused the unexpected increase in pertussis cases in the Netherlands despite high vaccination coverage?
Conclusion
The increase in pertussis cases in the Netherlands likely reflects a true outbreak, but the exact cause remains undetermined.
Supporting Evidence
- In 1996, 2,771 cases of pertussis were reported, a significant increase from 319 cases in 1995.
- Vaccine coverage for pertussis is 96% at the age of 12 months.
- The age distribution of patients showed a significant decrease in infants and an increase in older children.
- Changes in serodiagnostic practices may have influenced notification rates.
Takeaway
Even though many kids are vaccinated against whooping cough, a lot of them still got sick in the Netherlands, and we don't know why.
Methodology
The study analyzed pertussis notification data from 1989 to 1996 and compared case numbers across different years and age groups.
Potential Biases
Potential biases in reporting due to increased awareness and compliance after the outbreak was publicized.
Limitations
The study relies on notification data, which may be influenced by changes in reporting practices and underreporting.
Participant Demographics
The study included cases from various age groups, with a notable shift in the age distribution of reported cases over the years.
Want to read the original?
Access the complete publication on the publisher's website