Temporal trends in respiratory syncytial virus-related infant mortality and hospitalizations in the United States

BACKGROUND: Respiratory syncytial virus (RSV) is a leading cause of infant mortality and morbidity, yet national trends in RSV outcomes, particularly during the COVID-19 era, are not well defined. This study evaluated temporal patterns in RSV-related infant mortality and hospitalizations across the United States. METHODS: We analyzed RSV-associated infant mortality data from 2007-2022 using the CDC WONDER database and hospitalization rates from 2018-2025 using the hospitalization surveillance network (RSV-NET). Infant mortality and hospitalization patterns were assessed by season, race/ethnicity, and birth weight. RESULTS: Over 16 years, RSV-related infant mortality remained relatively stable, with no statistically significant year-to-year variation. Mortality rates were disproportionately higher among Black or African American infants and those with low birth weight. Seasonal hospitalization patterns varied substantially: the 2020-2021 RSV season recorded the lowest hospitalization rate, likely reflecting widespread COVID-19 mitigation measures, whereas the 2022-2023 season recorded the highest rate since 2018. CONCLUSION: Although infant RSV mortality has remained stable, persistent disparities exist, and hospitalization rates show substantial seasonal fluctuations. These findings provide critical baseline data for assessing the impact of emerging RSV immunization strategies and highlight the need for targeted strategies to reduce persistent inequities in infant outcomes in the post-COVID-19 era. IMPACT: RSV-related infant mortality in the United States has shown both stability and a sharp post-pandemic surge, with persisting disparities by sex, birthweight and race. This study integrates temporal, demographic, and geographic patterns to provide the national-level evidence of RSV mortality and hospitalization patterns among infants during COVID-19 era. These findings establish essential baseline estimates to evaluate effectiveness of preventive measures, while underscoring the urgency of targeted strategies to reduce disproportionate risks among vulnerable infants.