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Influenza Vaccine Effectiveness

The effectiveness of influenza vaccines

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3 results
Feb 7, 2026

How effective are 2025–2026 COVID-19 vaccines at preventing hospitalization and death by age group?

Real-world evidence from the 2024–2025 season—used to project likely performance of the 2025–2026 formulations—shows moderate protection against hospitalization and stronger protection against death o...

Feb 4, 2026

How do recombinant and cell‑culture flu vaccines differ from egg‑based vaccines in effectiveness and safety?

Recombinant and cell‑culture influenza vaccines are manufactured without eggs and therefore avoid egg‑adapted mutations that can alter the vaccine virus’s hemagglutinin antigen; immunologic and observ...

Jan 7, 2026

What are end‑of‑season, peer‑reviewed vaccine effectiveness estimates for 2025–26 by age and outcome (infection, medical attendance, hospitalization)?

Peer‑reviewed, end‑of‑season estimates specifically labeled “2025–26 end‑of‑season” remain limited in the literature, but a systematic NEJM review of studies through July 31, 2025 concluded that ongoi...