Resurgence of pertussis: Epidemiological trends, contributing factors, challenges, and recommendations for vaccination and surveillance.

Pertussis, a respiratory disease caused by Bordetella pertussis, remains a global health challenge despite decades of vaccination. The inclusion of diphtheria, tetanus, and whole-cell pertussis (DTwP) vaccines in the World Health Organization (WHO) Expanded Program on Immunization (EPI) in 1974 significantly reduced incidence worldwide. However, since the 1980s, pertussis resurgence has been observed in both high-income and low- and middle-income nations. The COVID-19 pandemic further disrupted vaccination, exacerbating outbreaks. Contributing factors include genetic mutations in Bordetella pertussis, vaccine differences, waning immunity, inadequate immunization, disease cyclicity, and the impact of the COVID-19 pandemic, coupled with improved surveillance, diagnostics, and awareness. Pertussis continues to impose a substantial disease burden, with infants being the most vulnerable. This review examines pertussis epidemiology from 1980 to 2023, analyzing resurgence drivers and evaluating current progress and persistent challenges in vaccination strategies and surveillance efforts.