Index/Topics/COVID-19 vaccine effectiveness

COVID-19 vaccine effectiveness

The effectiveness of COVID-19 vaccines, mentioned as an example of the CDC's use of the test-negative case-control design.

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5 results
Jan 13, 2026
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We’re health outcomes already improving before vaccinations

Before COVID-19 vaccines became widely available, some health indicators—case growth in places that successfully suppressed transmission and mortality in countries that expanded hospital capacity and ...

Jan 18, 2026
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When will CDC publish a U.S. vaccine effectiveness estimate for the 2025–26 season and how are those studies designed?

Public reporting from CDC and partner networks indicates there is no single fixed calendar date for a U.S. influenza vaccine effectiveness (VE) estimate for the 2025–26 season; instead CDC and its sur...

Jan 7, 2026
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When will the CDC release U.S.-specific midseason vaccine effectiveness estimates for 2025–2026?

There is no specific release date in the available reporting for U.S.-specific midseason influenza vaccine effectiveness (VE) estimates for 2025–2026; the CDC has published early and routine VE analys...

Jan 15, 2026

What does immunobridged mean

Immunobridging is a regulatory and scientific strategy that uses measurable immune responses as surrogate markers to infer how well a vaccine or antibody will protect people, allowing regulators to au...

Jan 11, 2026

How does flu vaccine effectiveness compare to natural immunity across different age groups?

Seasonal influenza vaccines provide moderate, variable protection that is generally higher in children than in adults and lower in older adults, while immunity from natural infection tends to be more ...