Objective:
To evaluate the effectiveness of the 2025-2026 COVID-19 vaccine in providing short-term protection against medically attended COVID-19 among immunocompetent adults.
Approach:
- Study Design: A test-negative case-control study using data from the VISION Network, assessing patients aged 18 years or older who sought care for COVID-19-like illness and underwent SARS-CoV-2 testing from September 3 to December 31, 2025.
- Data Collection: Data were collected from 253 emergency department and urgent care sites and 179 hospitals across 7 US states.
- Vaccine Effectiveness Estimation: Vaccine effectiveness was estimated by comparing the odds of vaccination among cases (positive SARS-CoV-2 test) versus controls (negative test), adjusting for demographic and geographic factors.
Key Findings:
- Vaccine effectiveness was estimated at 50% against COVID-19-associated emergency department and urgent care encounters, reflecting short-term early-season protection.
- Vaccine effectiveness was estimated at 55% against COVID-19-associated hospitalization, reflecting short-term early-season protection.
- Among patients aged 65 years or older, effectiveness was 48% for ED/UC encounters and 53% for hospitalizations, reflecting short-term early-season protection.
Interpretation:
The estimates should be interpreted as the added benefit of a 2025-2026 dose in a population with existing immunity, rather than a comparison between vaccinated and immunologically naive patients, based on the study's findings.
Limitations:
- Some patients may have sought care for reasons unrelated to COVID-19.
- Vaccination status may have been misclassified.
- Residual confounding from unmeasured factors may have influenced findings.
- Low hospitalization rates and vaccination rates limited statistical power.
- Findings may not be generalizable to all US patients.
Conclusion:
The study highlights the short-term effectiveness of the 2025-2026 COVID-19 vaccine in a population with high levels of immunity, based on the study's findings.
Sources:
This content is an AI-generated, fully rewritten summary based on a published scholarly article. It does not reproduce the original text and is not a substitute for the original publication. Readers are encouraged to consult the source for full context, data, and methodology.
