PLoS One

BackgroundInfluenza is an important contributor to acute respiratory illness, including pneumonia, and results in substantial morbidity and mortality globally. Understanding the local burden of influenza-associated severe disease can inform decisions on allocation of resources toward influenza control programs. Currently, there is no national influenza vaccination program in Uganda.MethodsIn this study, we used data on pneumonia hospitalizations that were collected and reported through the Health Management Information System (HMIS) of the Ministry of Health, Uganda, and the laboratory-confirmed influenza positivity data from severe acute respiratory illness (SARI) surveillance in three districts (Wakiso, Mbarara, and Tororo) to estimate the age-specific incidence of influenza-associated pneumonia hospitalizations from January 2013 through December 2016.ResultsThe overall estimated mean annual rate of pneumonia hospitalizations in the three districts was 371 (95% confidence interval [CI] 323\u2013434) per 100,000 persons, and was highest among children aged <5 years (1,524 [95% CI 1,286\u20131,849]) compared to persons aged 655 years (123 [95% CI 105\u2013144]) per 100,000 persons. The estimated mean annual rate of influenza-associated pneumonia hospitalization was 34 (95% CI 23\u201348) per 100,000 persons (116 [95% CI 78\u2013165] and 16 [95% CI 6\u201328] per 100,000 persons among children aged <5 years and those 655 years, respectively). Among children aged <5 years, the rate of hospitalized influenza-associated pneumonia was highest among those who were <2 years old (178 [95% CI 109\u2013265] per 100,000 persons). Over the period of analysis, the estimated mean annual number of hospitalized influenza-associated pneumonia cases in the three districts ranged between 672 and 1,436, of which over 70% represent children aged <5 years.ConclusionsThe burden of influenza-associated pneumonia hospitalizations was substantial in Uganda, and was highest among young children aged