Long-term trends in childhood mortality following the expansion of vaccination programs: a 60-year analysis from a university hospital in Rio de Janeiro State, Brazil.

Vaccination is one of the most important public health interventions, preventing an estimated five million deaths worldwide each year. This retrospective observational study analyzed hospitalizations and deaths among children aged 0 to 10 years admitted to a university hospital in the state of Rio de Janeiro, Brazil, over a sixty-year period (1965-2024). During the study period, 3968 children were hospitalized, and 779 deaths were recorded, with a predominance of males (55.6%). The overall mortality rate was 19.6%, being highest among children aged 0 to 1 year (28.9%), and lower among those aged 2 to 5 years (13.4%) and 6 to 10 years (11.9%). Hospitalizations and deaths were concentrated in the first two decades of observation, accounting for 64.2% and 86.6% of events, respectively. The highest mortality rate was observed in the first decade (29.2%), decreasing more than threefold from the third decade onward (9.4%) and approaching zero in the final years of analysis. Tetanus and meningoencephalitis accounted for more than half of all deaths, predominantly among children under one year of age (65.8%). Diphtheria and measles were the next most frequent causes of death, while whooping cough, although less common, was an important cause of mortality in early infancy. These findings highlight the substantial and sustained association between the expansion of immunization programs and the reduction of childhood hospitalizations and mortality from vaccine-preventable diseases. Maintaining high vaccination coverage remains essential to preserve these public health gains.