RESUMEN
BACKGROUND: Pneumococcal disease is a major public health concern globally and particularly in Burkina Faso, where the 13-valent pneumococcal conjugate vaccine (PCV13) was introduced nationwide into the routine immunization schedule in 2013. The aim of this study was to evaluate vaccine impact on all-cause pneumonia hospitalizations among children <5 years of age. METHODS: Hospitalization data covering a 10-year period (January 1, 2009-December 31, 2018) were collected retrospectively in four rural district hospitals, using medical records to extract data on relevant variables. Using an interrupted time-series design and segmented regression, the effectiveness and impact of PCV13 on the rates of pneumonia hospitalization were estimated. Severe acute malnutrition and unintentional injury were used as control conditions. RESULTS: Vaccine effectiveness was found to be 34% (95% confidence interval (CI) 16-49%, p=0.001), 24% (95% CI 2-41%, p=0.032), and 50% (95% CI 30-64%, p<0.001) against all-cause pneumonia among children <5 years, <2 years, and 2-4 years of age, respectively. By October 2018, PCV13 introduction had led to an absolute reduction in the pneumonia hospitalization rate of 348 cases per 100000 person-years among children <5 years of age. No decline was observed for the control conditions. CONCLUSIONS: These estimates point to a substantial public health impact of PCV13 against pneumonia hospitalization among children aged <5 years in Burkina Faso.