Pertussis is an acute respiratory infection, highly contagious, caused by Bordetella pertussis, mainly affecting infants and children who are unvaccinated or have incomplete vaccination schedules. Although vaccination has significantly reduced global incidence and mortality, outbreaks still occur. This study aimed to describe the recent increase in pertussis cases in Brazil. A descriptive, retrospective, quantitative study based on data from epidemiological bulletins of the Ministry of Health and SINAN notifications from 2021 to 2024. The number of confirmed cases, case fatality, and geographic distribution were analyzed. Additionally, vaccination coverage for Pentavalent (3 doses in the first year of life) and adult dTpa in 2024 was assessed using Tabnet and the national vaccination panel, seeking to correlate these indicators with disease incidence. Between 2021 and 2023, Brazil recorded low numbers of pertussis cases (159, 237, and 216, respectively), all without deaths. In 2024, however, a marked increase was observed, with 7,545 reported cases and a case fatality of 0.8%, representing the highest number in a decade. The most affected states were Paraná (2,822 cases), São Paulo (1,701), and Minas Gerais (856). National average vaccination coverage in 2024 was approximately 86% for Pentavalent and 82% for adult dTpa, below the recommended 95%. Some states with higher incidence showed moderate coverage, suggesting an accumulation of susceptible individuals over the years which, coupled with the resumption of in-person activities after the pandemic and the cyclical behavior of the disease, may have favored the current outbreak. The sharp increase in pertussis cases in 2024 highlights the need to strengthen National Immunization Program strategies, intensify epidemiological surveillance actions, and raise public awareness about the importance of complete vaccination schedules. These findings reiterate the impact of low coverage on transmission dynamics and reinforce the importance of continuous monitoring to prevent new outbreaks and reduce pertussis-related morbidity and mortality.
Silva et al. (Sun,) studied this question.