Tracking vaccination coverage and pertussis incidence in Brazil before and after dTPA vaccine implementation

Abstract Pertussis (or whooping cough) is an acute infectious disease of respiratory tract. The introduction of pertussis vaccination has substantially reduced incidence rates and mortality associated with the disease. Despite the vaccination, pertussis has reemerged in several countries, particularly affecting infants under six months of age. In November 2014, the Brazilian Ministry of Health (BMH) implemented the tetanus-reduced diphtheria toxoid-acellular pertussis (dTpa) vaccine, targeting individuals at high risk such as pregnant women and healthcare professionals. Here, we evaluated the incidence of pertussis and vaccination coverage during a period of 17 years, before and after the introduction of dTpa. An observational, ecological time-series study was conducted using secondary data collected from the National Notifiable Diseases Information System (SINAN). Descriptive statistics and regression analysis to estimate increases or reductions in the mean incidence over time were performed. Our findings highlight the implications regarding shifts in disease incidence, the importance of continuous surveillance, and supporting strategies for pertussis prevention and control, mainly focused on strengthening vaccination strategies and increasing vaccination awareness and coverage.