Estimating the burden of adult hospitalized RSV infection including special populations

BackgroundNumerous studies in the U.S. have made estimates of the RSV burden among adults that vary widely due to differences in methodology, reliance on influenza surveillance, which does not adequately capture all RSV clinical symptoms, and lack of diagnostic methods to identify RSV when viral loads are low. Nevertheless, accurate burden estimates can inform healthcare planning, resource allocation and potentially, RSV vaccine policy.MethodsA simple method combined with statewide and local hospitalization, medical record and U.S. Census data were used to estimate population-based RSV hospitalization burden among adults ages 18–64 years, ≥65 years, and including immunocompetent, immunocompromised and pregnant individuals during 2015–2018 for Allegheny County, Pennsylvania. Economic burden of hospitalization was estimated using state-provided average hospitalization charges for comparisons across patient groups.ResultsThe largest burden was borne by adults ≥ 65 years of age whose rates per 100,000 population of that age group (939/100,000) were 7.0–9.0 times those of adults 18–64 years of age (118/100,000). Immunosuppressed patients bore the greatest relative burden of RSV hospitalizations (1,288–1,562/100,000 immunosuppressed individuals). RSV burden ranged from 0 to 808/100,000 pregnant women. Average total charges for RSV hospitalization in Allegheny County across all adults increased from $39 million in 2015–2016 to $57 million in 2016–2017 to $89 million in 2017–2018, due to both increased average charges for an acute respiratory hospitalization and increased numbers of RSV cases.ConclusionsThese RSV burden estimates add to the body of knowledge to guide public health policy makers and offer a method for simply and easily producing population-based burden estimates.