The immunity provided by the whooping cough (pertussis) vaccine typically wanes over time. Protection after vaccination usually lasts about 4 to 7 years, with evidence showing that vaccine effectiveness begins to significantly decline beyond 4 years and offers little to no protection after about 7 years. Some studies suggest the odds of contracting pertussis increase roughly 27% each year after vaccination, and immunity following natural infection lasts longer, roughly 7 to 20 years. The acellular pertussis vaccine currently used tends to provide shorter immunity than the older whole-cell vaccine. Booster doses are recommended to maintain protection, especially in adults and pregnant women to protect newborns. Key points on duration of immunity for whooping cough vaccine:
- Immunity after vaccination lasts approximately 5 to 7 years, with significant waning after 4 years.
- Immunity after natural infection can last 7 to 20 years.
- Protection from the acellular vaccine wanes faster than from the older whole-cell vaccine.
- Booster doses are recommended every 10 years for adults and during pregnancy for infant protection.
- The vaccine is most effective within the first few years post-vaccination and should be repeated to maintain immunity.
This information is consistent with current public health recommendations and research findings.
