Understanding why some vaccinated individuals still get Covid-19

VAccine failure: natural history and determinants of post-vaccination Covid-19

NIH-funded research Veterans Affairs Med Ctr San Francisco · NIH-11044121

This study is looking at why some veterans aged 65 and older still get sick with Covid-19 even after being vaccinated, and it aims to learn more about how well the vaccine works over time.

Quick facts

Grant typeNIH-funded research
Study typeNIH-funded research
Funding institutionVeterans Affairs Med Ctr San Francisco NIH-funded
Lab location1 site (San Francisco, United States)
Project IDNIH-11044121 on NIH RePORTER

What this research studies

This research investigates the phenomenon of vaccine failure in individuals who have received Covid-19 vaccinations but still develop symptomatic disease. It aims to identify the clinical outcomes and factors that contribute to these cases, particularly focusing on veterans aged 65 and older. By utilizing real-time data from the Veterans Health Administration, the study will create a national cohort to monitor and analyze the epidemiology of post-vaccination Covid-19. The goal is to enhance understanding of how vaccine effectiveness may change over time and under different conditions.

Who could benefit from this research

Good fit: Ideal candidates for this research are veterans aged 65 and older who have received at least one dose of a Covid-19 vaccine and had a primary care visit in the past two years.

Not a fit: Patients who are younger than 65 years or those who have not received any Covid-19 vaccinations may not benefit from this research.

Why it matters

Potential benefit: If successful, this research could lead to improved vaccination strategies and better protection for older adults against Covid-19.

How similar studies have performed: While there have been studies on vaccine efficacy, this specific focus on vaccine failure in older adults is relatively novel and aims to fill a critical gap in understanding.

Where this research is happening

San Francisco, United States

Researchers

About this research

  1. This is an active NIH-funded research project — typically early-stage science, not a clinical trial accepting patient enrollment.
  2. Some NIH-funded labs run parallel clinical studies or seek volunteers for related work. To check, contact the principal investigator or institution listed above.
  3. For full project details, budget, and progress reports, visit the official NIH RePORTER page below.
Last reviewed 2026-06-13 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.