Are COVID-19, RSV, and Influenza vaccines safe and effective?

This study presents a systematic review and meta-analysis of the effectiveness and safety of immunizations against three major respiratory viruses: Covid-19, respiratory syncytial virus (RSV), and influenza. Authored by a large team of researchers and published in the New England Journal of Medicine, the article synthesizes evidence to provide independent guidance for the 2025–2026 respiratory virus season. Key findings indicate that vaccinations generally provide substantial protection against severe outcomes like hospitalization, though effectiveness varies by vaccine type, virus subvariant, and population (e.g., immunocompromised adults). The review also details specific safety profiles, noting rare adverse events like myocarditis associated with Covid-19 vaccines and Guillain–Barré syndrome with one RSV vaccine in older adults.