Costs associated with acute respiratory illness and select virus infections in hospitalized children, El Salvador and Panama, 2012–2013

•Median cost per severe acute respiratory illness (ARI) was US$219–$393.•Median cost per severe ARI was equal to 43–79% of national health expenses per capita.•Severe ARIs requiring intensive care cost 5–8 times more than those that did not.•Caregivers bore approximately one fourth of costs of severe ARI.•Severe ARI frequently resulted in lost work days and wages for caregivers. Although acute respiratory illness (ARI) is a leading cause of hospitalization among young children, few data are available about cost of hospitalization in middle-income countries. We estimated direct and indirect costs associated with severe ARI resulting in hospitalization among children aged