Correlates of risk of respiratory syncytial virus disease: a prospective cohort study
Abstract
Few population-based studies have evaluated the importance of pre-existing respiratory syncytial virus (RSV) antibody on RSV susceptibility among children and adults. We conducted a prospective, community-based cohort study among individuals aged 6 months-50 years in Oregon and Washington State, USA (June 2022-May 2023), with weekly symptom surveys and swab collection regardless of symptoms. Swabs were tested for RSV using RT-qPCR. Enrollment sera were tested for RSV prefusion F IgG binding (all participants) and neutralizing antibodies (pediatric participants). We detected 305 RSV illnesses among 3237 participants from 1188 households. Using proportional hazards regression, higher RSV binding antibody titers were associated with a lower estimated hazard of RSV among pediatric participants (hazard ratio=0.66 per 1-unit difference in log10-RSV antibody titer; 95% CI: 0.56, 0.78). In a post-pandemic period, pre-existing RSV antibody titers were associated with a lower risk of RSV illness in children aged 6 months-17 years, which could inform vaccine development for this age group.