Vaccine Expert Relishes Roles in Research, Policy 

Zimmerman, professor of family medicine in the University of Pittsburgh School of Medicine and professor of clinical epidemiology in the Department of Behavioral and Community Health Sciences at Pitt's School of Public Health, has worked with the CDC’s Advisory Committee on Immunization Practices in a variety of roles for nearly 30 years.

“I have always loved the intersection between science and health policy,” he said. “It is the way I’m wired. My initial goals as an ACIP liaison was to transmit the evidence-based family medicine perspective to the ACIP and to bring back to AAFP and (the Society of Teachers of Family Medicine) the latest vaccine science and policy.”

After serving as the AAFP’s liaison to the committee, Zimmerman was asked by the CDC to become a voting member. In that role, he served as chair of the ACIP’s influenza and adult immunization working groups. He also has worked with the committee as a consultant.

“The opportunity to assist with vaccine policy that affects care for our population is an incredible privilege,” he said. “It is a lot of work. I learned about disease epidemiology, vaccine science and public policy decision-making.”

Zimmerman graduated from the Grant Family Medicine Residency in Columbus, Ohio, in 1989. Two years later, he finished a second residency in general preventive medicine and public health at the University of Minnesota School of Public Health. That same year at the University of Minnesota, he completed a fellowship in academic medicine and clinical investigation and a master’s degree in public health.

“I think that the U.S. health care system, and family medicine in particular, need to have training in health policy decision-making,” said Zimmerman, who served on the University of Pittsburgh Medical Center COVID-19 Vaccine Advisory Group, which serves a health system with 40 hospitals. “We also need adequate public health surveillance tools and strong informatics to analyze information quickly. We also need to study the public uptake of preventive measures and how we can facilitate that.”

Zimmerman’s father, Willis Zimmerman, D.O., was a primary care physician in Toledo for 40 years and also served as chief of staff for a local hospital and director of a family medicine residency program. During his own residency at Grant, Zimmerman rotated with his father, who stressed immunizations in his practice.

But the younger Zimmerman recalled a much earlier memory that raised his awareness of the importance of immunizations and vaccine-preventable diseases. His Sunday-school teacher, who also was family friend, developed paralytic polio as an adult. 

“Back in the days before handicap accessible facilities, he went on his crutches down the steps of an old church for my Eagle Scout banquet,” Zimmerman said. “He was quite a man, but he suffered greatly from post-polio syndrome.”

As a student at the Ohio State College of Medicine,  Zimmerman traveled to Africa for a rotation in Swaziland (now Eswatini). There he worked on a rural health survey regarding a mission clinic, and vaccines played a prominent role in that project.

Nearly 40 years later, he’s still working on vaccine-related projects. 

• Zimmerman was a leader in developing the Shots Immunizations App. That tool from the AAFP and STFM offers the latest guidance from the ACIP regarding adult and childhood immunization schedules.
• He led the University of Pittsburgh group that developed the 4 Pillars Practice Transformation Program, which offers evidence-based, step-by-step guidance to improve immunization rates in outpatient settings.
• His published data regarding cost barriers to vaccinations has been used by the CDC to defend the Vaccines for Children program in Congress.
• Zimmerman has been the Pittsburgh lead for two CDC networks: The outpatient U.S. Flu Vaccine Effectiveness Network and its inpatient counterpart, the Hospitalized Adult Influenza Vaccine Effectiveness Network. The work of these networks directly contributed to the World Health Organization’s decision to change the influenza vaccine strain composition for the northern hemisphere in 2019. The networks also documented that live attenuated influenza vaccine was not effective against influenza type A, leading to the nasal spray’s temporary removal from the U.S. market in 2016.

Those CDC Networks also have tracked COVID vaccine effectiveness data, which have been published and shared with the ACIP.

“The most satisfying part of serving as an immunization expert during the pandemic was to use my expertise, training and experience to help others by formulating policy at the local level,” he said. “In my institutions, I provided clinician education on how policy is made and the care with which it is made, and provided education to the public on COVID, COVID vaccines and health policy.”

Conversely, Zimmerman said the most challenging aspects of the pandemic were the speed of the virus’ spread and the vast amount of information that had to be digested. Clinicians faced vaccine hesitancy often based on false information or “alternative views on the truth” in a nation with limited health literacy, he said.

Family physicians, however, can make a difference.

“Changing beliefs is very difficult” he said. “I think that reasoned answers, compassion and direct messaging about the fact that the physician recommends the vaccine for this particular patient at this time is key, period. Also, physicians and their staff should be vaccinated to set the example.”

Although his father was a primary care physician, Zimmerman said it was a fourth-year rotation in Mansfield, Ohio, that led him to choose family medicine. Family physicians Bill Geiger, M.D., and Terry Weston, M.D., invited Zimmerman not only into their practice, but also their homes.

“These doctors practiced family medicine in a way that was holistic, accounting for the physical, psychological and spiritual concerns of their patients,” Zimmerman said. “This whole-person approach appealed to me, in contrast to some other approaches that would deal primarily with a particular body part. For these two family physicians there was a genuineness in their lives that went from their home life to their practice, and because they allowed me to stay in their homes, I could see that in both places. They both had a strong spiritual foundation that guided them.”