Objective:

To evaluate the vaccine effectiveness (VE) and durability of the BNT162b2 KP.2 vaccine against COVID-19 hospitalizations and emergency department visits among adults aged 18 and older in the United States.

Key Findings:

• Vaccine effectiveness against hospital admissions was 49% (95% CI, 30–63) (<3 months) and waned to 35% (95% CI, 8–54) (≥3 months).
• Vaccine effectiveness against emergency department visits was 45% (95% CI, 35–54) (<3 months) and waned to 26% (95% CI, 12–38) (≥3 months).
• Protection persisted beyond 90 days post-vaccination, with some waning observed.

Interpretation:

The BNT162b2 KP.2 vaccine provides significant protection against COVID-19 hospitalizations and emergency care visits, with sustained effectiveness observed in older adults and regardless of prior vaccination history, highlighting its importance in public health strategies.

Limitations:

• The study was limited to a single health system, which may affect generalizability and the applicability of results to broader populations.
• Data on prior COVID-19 vaccination status was not available for all age-stratified analyses, potentially limiting the understanding of vaccine effectiveness across different demographics.

Conclusion:

The BNT162b2 KP.2 vaccine demonstrates substantial effectiveness against COVID-19-related hospitalizations and emergency visits, supporting ongoing vaccination efforts, particularly among older adults, to enhance community health resilience.