1719 - Respiratory Syncytial Virus-Associated Hospitalization Rates among US Infants: A Systematic Review and Meta-Analysis

Background: Understanding the true magnitude of infant respiratory syncytial virus (RSV) burden is critical for determining the potential public-health benefit of RSV prevention strategies. Although global reviews of infant RSV burden exist, none have summarized data from the United States or evaluated how RSV burden estimates are influenced by variations in study design.

Methods: We performed a systematic literature review and meta-analysis of studies describing RSV-associated hospitalization rates among US infants. We also examined the impact of key study characteristics on these estimates.

Results: After review of 3058 articles through January 2020, we identified 25 studies with 31 unique estimates of RSV-associated hospitalization rates. Among US infants < 1 year of age, annual rates ranged from 8.4 to 40.8 per 1000 with a pooled rate= 19.4 (95%CI= 17.9–20.9). Study type was associated with RSV hospitalization rates (P =.003), with active surveillance studies having pooled rates per 1000 (11.1; 95%CI: 9.8–12.3) that were half that of studies based on administrative claims (21.4; 95%CI: 19.5–23.3) or modeling approaches (23.2; 95%CI: 20.2–26.2).

Conclusion: Applying the pooled rates identified in our review to the 2020 US birth cohort suggests that 73,680 to 86,020 RSV-associated infant hospitalizations occur each year. To date, public-health officials have used conservative estimates from active surveillance as the basis for defining US infant RSV burden. The full range of RSV-associated hospitalization rates identified in our review better characterizes the true RSV burden in infants and can better inform future evaluations of RSV prevention strategies.