The Westat Team Behind VISION’s Success

The VISION Vaccine Effectiveness Network, launched by the Centers for Disease Control and Prevention (CDC) in 2020, spurred a monumental shift in vaccine assessment, guiding COVID-19 vaccine policy decisions and delivering critical information about this disease to Americans quickly. Westat’s coordination of this collaborative “virtual network” of 9 integrated U.S. health systems enabled delivery of timely, robust data on vaccine effectiveness for different populations in different real-world conditions, and greatly expanded knowledge about COVID-19’s outcomes and complications. This research was vital to helping the nation battle this deadly pathogen.

Strong Team Ethos

Integral to the success of this expansive public health effort was Westat’s team of skilled professionals. Key among them were Sarah Ball, ScD, MS, MPH, Vice President and Lead Scientific/Epidemiology Advisor, who managed the project, and Elizabeth A. K. Rowley, DrPH, a Principal Statistical Associate, who served as a co-analytic lead.

As project director, Ball managed multiple responsibilities, including collaborating with the 9 partner sites, ensuring the seamless integration of population-based surveillance and electronic health records (EHRs), and overseeing the rapid data analysis and biweekly reporting required by CDC. When CDC shifted priorities, Ball made certain that her team quickly adapted, and when staff members needed to shift gears, she had them focus on other priorities.

“I was able to be flexible,” she said, “because we had a very capable, collaborative team that was large enough to assume the responsibilities of those needing time off or to attend to other tasks.”

Ball also managed the budget, maintained frequent contact with CDC, provided high-level input related to scientific responsibilities, and supervised publication of Westat’s findings. She shakes off compliments of her role in VISION, pointing to the collaborative CDC and health systems partnerships and her team’s unwavering commitment to the research.

“We all saw how valuable and rewarding this work was—that it was contributing to positive outcomes for the public,” she said. “And we saw rapid publication of our findings, so it was easy to overlook all the challenges for the greater good.”

Rowley wrote the initial code to analyze the data and oversaw the translation of scientific questions impacting programming. She developed a statistical analysis pipeline to quickly analyze biweekly data deliveries from health systems and produce reports for decisionmakers essential to determining national COVID-19 vaccine policy. She also performed simulation studies into various analytic techniques to determine which ones would guarantee that the data could translate into a clear understanding of vaccine effectiveness.

Insightful, Valuable Findings

The VISION Network published over 25 papers, both in peer-reviewed journals and in CDC’s Morbidity and Mortality Weekly Report (MMWR). These publications provided scientists with the latest information about the effectiveness of the COVID-19 vaccines and gave policymakers the insights and actionable data they needed to make informed decisions. Data that was relayed in close to real time over the course of the project included:

• The effectiveness of the vaccines against initial and later subvariants
• Vaccine effectiveness among pregnant persons, immunocompromised people, and children and youth 5-17 years old
• Waning effectiveness of monovalent vaccines
• Impact of COVID-19 vaccines on attenuating disease severity
• Effectiveness of the bivalent booster

Other publications produced by the VISION team reported on vaccine coverage and effectiveness by social vulnerability; protection from mRNA vaccination and prior infection against COVID-associated medical encounters; the number of people needed to vaccinate to prevent COVID-associated medical encounters; and the effectiveness of the 2021-22 influenza vaccine.

“The impact of our work was stunning,” Rowley said, noting that “almost immediately” Westat’s findings were presented to CDC’s Advisory Committee on Immunization Practices, which developed recommendations on vaccine use for various population segments. “But,” she adds, “as the pandemic evolved and CDC’s requirements pivoted, we needed to update our analyses every 2 weeks. This involved analysis of an enormous dataset of millions of COVID tests and vaccine records. It also meant continuously reviewing the data or changing the way we reported them to CDC to ensure absolute clarity. Our adaptability, strong team unity, and deep commitment to the work enabled us to deftly manage the project’s multiple moving parts.”

New Research Opportunities

In July 2023, Westat was awarded the VISION 2.0 contract, which is focused not only on COVID-19, but also on flu and respiratory syncytial virus (RSV) vaccine effectiveness. The pace is slower than during the pandemic, with data analyzed and reported monthly. A report on the interim effectiveness estimates of the season’s COVID-19 and flu vaccines can be found in the February 2024 MMWR.

What’s next for VISION? Ball says the platform will be used to survey Lyme disease and vaccines to prevent it. “We are always looking for ways to make VISION’s capabilities and processes work in new and needed areas of investigation.”

Both Ball and Rowley applaud CDC’s leadership and engagement of Westat to conduct research that has saved so many lives and created the infrastructure to understand and defeat other pathogens that might emerge.