Pneumonia was diagnosed with chest radiography, and interpretation was accepted as written in the medical charts of patients, reporting either lobar pneumonia or bronchopneumonia, and empyema with or without pneumothorax. These reports are aligned to the WHO Standard for reporting chest radiographs in which there is presence of a dense or fluffy opacity that occupies a portion or whole of a lobe or of the entire lung, presence of fluid in the lateral pleural space between the lung and chest wall, or both.10 ,11 (link)The endpoints were number of pneumonia hospitalizations and deaths among children 3–24-month-old. The proportion of pneumonia hospitalizations was calculated before and after vaccination periods. The case-fatality rates were calculated from the deaths among the pneumonia admissions.