Article Impact Level: HIGH Data Quality: STRONG Summary of JAMA Internal Medicine. https://doi.org/10.1001/jamainternmed.2024.1640 Dr. Sara Y. Tartof et al.
Points
- Researchers assessed the effectiveness of the BNT162b2 XBB COVID-19 vaccine (Pfizer-BioNTech; 2023-2024 formulation) in a test-negative case-control study within the Kaiser Permanente Southern California health system, including 2,854 COVID-19 positive cases and 15,345 negative controls from October to December 2023.
- The BNT162b2 XBB vaccine administered a median of 34 days prior, showed 62% effectiveness (95% CI, 32%-79%) against COVID-19 hospitalizations and 58% effectiveness (95% CI, 48%-67%) against emergency department (ED) or urgent care (UC) visits.
- Individuals who had only received older COVID-19 vaccine versions did not exhibit a significant reduction in the risk of COVID-19 outcomes, including hospital admissions, compared to unvaccinated individuals.
- The study highlights the critical role of annually updated COVID-19 vaccines in significantly reducing the risk of severe COVID-19 outcomes, underscoring the limited long-term protection offered by older vaccine formulations.
- These findings support current public health recommendations for the broad, age-based administration of updated annual COVID-19 vaccines to combat the evolving virus and protect public health effectively.
Summary
In a test-negative case-control study conducted within the Kaiser Permanente Southern California health system, researchers assessed the effectiveness of the recently recommended BNT162b2 XBB COVID-19 vaccine (Pfizer-BioNTech; 2023-2024 formulation) among US adults. From October to December 2023, the study included 2,854 cases and 15,345 controls, all adults presenting with acute respiratory illnesses, with cases confirmed positive for SARS-CoV-2 and controls testing negative. The study aimed to compare the effectiveness of the BNT162b2 XBB vaccine against COVID-19-related hospital admissions and emergency department (ED) or urgent care (UC) visits, with a particular focus on determining the additional protection offered by the BNT162b2 XBB vaccine over not receiving any XBB vaccine, as well as evaluating the residual effectiveness of older vaccine formulations.
The findings indicated significant additional protection conferred by the BNT162b2 XBB vaccine, administered a median of 34 days prior to evaluation. The adjusted effectiveness of the BNT162b2 XBB vaccine was 62% (95% CI, 32%-79%) against COVID-19 hospitalizations and 58% (95% CI, 48%-67%) for ED/UC visits. In contrast, those who had received only older versions of COVID-19 vaccines did not exhibit a statistically significant reduction in risk for COVID-19 outcomes compared to unvaccinated individuals, including for hospital admissions.
The study substantiates the importance of utilizing annually updated COVID-19 vaccines, demonstrating that the BNT162b2 XBB vaccine significantly reduces the risk of severe COVID-19 outcomes. Older vaccine versions, irrespective of the number or type of prior doses received, showed little to no long-term protection against COVID-19, particularly for hospital admissions. These results reinforce current public health recommendations advocating for broad, age-based administration of updated annual COVID-19 vaccines to combat the evolving virus and protect public health effectively.
Link to the article: https://jamanetwork.com/journals/jamainternalmedicine/fullarticle/2820268
References Tartof, S. Y., Slezak, J. M., Frankland, T. B., Puzniak, L., Hong, V., Ackerson, B. K., Stern, J. A., Zamparo, J., Simmons, S., Jodar, L., & McLaughlin, J. M. (2024). Estimated Effectiveness of the BNT162b2 XBB Vaccine Against COVID-19. JAMA Internal Medicine. https://doi.org/10.1001/jamainternmed.2024.1640
