September 17, 2026

RSV

RSV Immunization Effectiveness and Safety for the 2026-2027 Respiratory Season
Embase, Cochrane CENTRAL, and Scopus were searched from August 1, 2025, through June 29, 2026, for studies evaluating the safety and effectiveness of U.S.-licensed RSV vaccines or RSV monoclonal antibody products or describing RSV epidemiology. A total of 75 eligible studies were identified, including 12 randomized clinical trials (RCTs), 33 observational studies with a comparator group, 16 observational studies without a comparator group, and 14 descriptive studies on RSV epidemiology. RSV immunizations were associated with reduced risk of severe RSV and RSV-related hospitalizations; evidence among older adults suggests that RSV VE may be lower in subsequent seasons. Reported adverse events of special interest (including GBS and preterm birth) were consistent with prior reviews. None of the comparative studies included in this review found an association of RSV vaccination during pregnancy with preterm birth or other adverse pregnancy outcomes. immunizations.

COVID: Active Vaccination/Immunity

COVID-19 Vaccine Effectiveness and Safety for the 2026-2027 Respiratory Season
This is a systematic evidence review. Cochrane Central Register of Controlled Trials, PubMed/MEDLINE, Embase, and Scopus were searched from August 1, 2025, through June 29, 2026. Studies were eligible if they reported on the effectiveness, efficacy, or safety of a U.S.-licensed COVID-19 vaccine or SARS-CoV-2 epidemiology in the U.S. From 11,829 identified references, 155 publications were eligible (15 randomized clinical trials, 84 observational studies with a comparator group, 38 product safety studies without a comparator group [single group], and 18 descriptive studies of disease burden). Conclusions: COVID-19 vaccines continue to reduce the risk of severe disease and hospitalization among all age groups and particularly among populations at higher risk for severe outcomes, including older adults, infants, and children. The benefits of vaccination vary by outcome and population, generally reducing the risk of severe adverse outcomes by 50% or more. These findings reinforce the importance of vaccination in preventing serious COVID-19 outcomes and highlight the value of continued evaluation of emerging evidence to inform up-to-date vaccination policies.