Rates of Medically Attended RSV Among US Adults: A Systematic Review and Meta-analysis

Abstract

Background: Adult respiratory syncytial virus (RSV) vaccines are in the late stages of development. A comprehensive synthesis of adult RSV burden is needed to inform public health decision-making.

Methods: We performed a systematic review and meta-analysis of studies describing the incidence of medically attended RSV (MA-RSV) among US adults. We also identified studies reporting nasopharyngeal (NP) or nasal swab reverse transcription polymerase chain reaction (RT-PCR) results with paired serology (4-fold-rise) or sputum (RT-PCR) to calculate RSV detection ratios quantifying improved diagnostic yield after adding a second specimen type (ie, serology or sputum).

Results: We identified 14 studies with 15 unique MA-RSV incidence estimates, all based on NP or nasal swab RT-PCR testing alone. Pooled annual RSV-associated incidence per 100 000 adults ≥65 years of age was 178 (95% CI, 152‒204; n = 8 estimates) hospitalizations (4 prospective studies: 189; 4 model-based studies: 157), 133 (95% CI, 0‒319; n = 2) emergency department (ED) admissions, and 1519 (95% CI, 1109‒1929; n = 3) outpatient visits. Based on 6 studies, RSV detection was ∼1.5 times higher when adding paired serology or sputum. After adjustment for this increased yield, annual RSV-associated rates per 100 000 adults age ≥65 years were 267 hospitalizations (uncertainty interval [UI], 228‒306; prospective: 282; model-based: 236), 200 ED admissions (UI, 0‒478), and 2278 outpatient visits (UI, 1663‒2893). Persons <65 years with chronic medical conditions were 1.2-28 times more likely to be hospitalized for RSV depending on risk condition.

Conclusions: The true burden of RSV has been underestimated and is significant among older adults and individuals with chronic medical conditions. A highly effective adult RSV vaccine would have substantial public health impact.

Keywords: burden; incidence; pooled; summary; underestimated.

Figure 1.

Flow diagram of the literature selection process. ^aOf the 14 studies, 1 study reported >1 RSV incidence of adults based on within-study variations or sensitivity analyses, for a total of 15 unique published incidence estimates in our analysis population. Abbreviation: RSV, respiratory syncytial virus.