Multistate study examines mRNA vaccine effectiveness for immunocompromised adults during Omicron BA.4 and BA.5 predominance

INDIANAPOLIS -- A new study from the Centers for Disease Control and Prevention’s VISION Network presents and analyzes some of the first real-world data on mRNA COVID vaccine effectiveness during Omicron BA.4 and BA.5 predominance for immunocompromised adults. The large, geographically diverse study confirms that overall protection provided by vaccination -- even with one, or later two, boosters -- for this population was lower than vaccine effectiveness for adults without immunocompromising conditions. Vaccine effectiveness was lowest among individuals with solid organ or stem cell transplants or hematologic malignancies such as leukemia, lymphoma, or multiple myeloma. BA.4 and BA.5 are the strains that are currently dominant and spreading.

The multistate study includes data from spring and summer 2022 when BA.4 and BA.5 Omicron subvariants became dominant and a total of four vaccine doses (two primary and two booster doses) was available to adults with immunocompromising conditions. The determination of lower vaccine effectiveness among individuals in this high-risk group suggests that non-pharmaceutical interventions, including masks, prophylactic antibody treatment, and anti-viral treatment after acquisition of the virus are important tools to consider for additional protection against severe COVID-19 in immunocompromised adults.

A review of the medical records of 30,000 immunocompromised adults found protection against COVID-19 associated hospitalizations was 34 percent after two vaccine doses, increasing to 71 percent during days 7 to 89 after a third dose, then declining to 41 percent 90 days or more after that dose. Although immunocompromised adults received increased protection after a third dose of the vaccine, this study found that vaccine effectiveness in this population remains lower than in the larger population of all adults.

“This study confirms that even with boosters, immunocompromised adults, because of their weakened immune systems, are still at high risk of moderate to severe COVID. While vaccines in the general adult population have been found to be 70 to 90 percent effective, for the immunocompromised we’re looking at a much lower range -- 34 to 71 percent effective,” said study co-author Brian Dixon, PhD, MPA, of the Regenstrief Institute and Indiana University Richard M. Fairbanks School of Public Health. “Those with healthy immune systems should keep in mind that we are a community with a responsibility to keep fellow community members, who are immunocompromised or have other conditions that place them at higher risk for COVID, even with vaccination, protected by taking precautions like hand hygiene and mask wearing, especially when transmission rates are high. We need to look out for one another.”

“This higher risk group has been taking precautions and should continue to work with their providers to access needed tools to protect themselves. Immunocompromised individuals should consult their physician with any questions regarding remaining up-to-date with COVID vaccinations to optimize their protection,” said Shaun Grannis, M.D., M.S., of the Regenstrief Institute and Indiana University School of Medicine. “Adults with immunocompromising conditions and other populations have specific questions about the pandemic and vaccine effectiveness. Our findings in this study are a step forward in helping to answer these questions.”

“Effectiveness of COVID-19 mRNA Vaccines Against COVID-19–Associated Hospitalizations Among Immunocompromised Adults During SARS-CoV-2 Omicron Predominance — VISION Network, 10 States, December 2021—August 2022" is published in the CDC’s Morbidity and Mortality Weekly Report and was funded by the CDC.

The CDC collaborated with seven U.S. healthcare systems plus the Regenstrief Institute to create the VISION Network to assess COVID-19 vaccine effectiveness. In addition to Regenstrief, other members are Columbia University Irving Medical Center, HealthPartners, Intermountain Healthcare, Kaiser Permanente Northern California, Kaiser Permanente Northwest, University of Colorado and Paso Del Norte Health Information Exchange (PHIX). Regenstrief contributes data and scientific expertise to the VISION Network.

Regenstrief Institute authors of this VISION Network study, in addition to Drs. Dixon and Grannis, are William F. Fadel, PhD, Nimish Ramesh Valvi, DrPH, MBBS, and former Institute president and current affiliate scientist Peter Embi, M.D.

Complete author list

Amadea Britton, M.D., Centers for Disease Control and Prevention COVID-19 Response Team; Peter J. Embi, M.D., M.S., Regenstrief Institute, Indiana University School of Medicine, Vanderbilt University Medical Center; Matthew E. Levy, PhD, Westat; Manjusha Gaglani, MBBS, Baylor Scott & White Health, Texas A&M University College of Medicine; Malini B. DeSilva, M.D., MPH, HealthPartners Institute; Brian E. Dixon, PhD, MPA, Regenstrief Institute, IU Richard M. Fairbanks School of Public Health; Kristin Dascomb, M.D., PhD, Intermountain Healthcare; Palak Patel, MBBS, MPH, Centers for Disease Control and Prevention COVID-19 Response Team; Kristin E. Schrader, M.A., Westat; Nicola P. Klein, M.D., PhD, Kaiser Permanente Northern California Division of Research; Toan C. Ong, PhD, University of Colorado Anschutz Medical Campus; Karthik Natarajan, PhD, Columbia University Irving Medical Center, New York-Presbyterian Hospital; Emily Hartmann, MPP, Paso del Norte Health Information Exchange (PHIX); Anupam B. Kharbanda, M.D., Children's Minnesota; Stephanie A. Irving, MHS, Center for Health Research, Kaiser Permanente Northwest; Monica Dickerson, B.S., Centers for Disease Control and Prevention COVID-19 Response Team; Margaret M. Dunne, MSc, Westat; Chandni Raiyani, BDS, MPH, Baylor Scott & White Health; Shaun J. Grannis, M.D., M.S., Regenstrief Institute, IU School of Medicine; Edward Stenehjem, M.D., MSc, Intermountain Healthcare; Ousseny Zerbo, PhD, Kaiser Permanente Northern California Division of Research; Suchitra Rao, MBBS, MSCS, University of Colorado Anschutz Medical Campus; Jungmi Han, B.S., Columbia University Irving Medical Center; Chantel Sloan-Aagard, PhD, Paso del Norte Health Information Exchange (PHIX), Brigham Young University Department of Public Health; Eric P. Griggs, MPH, Centers for Disease Control and Prevention COVID-19 Response Team; Zachary A. Weber, PhD, M.S., Westat; Kempapura Murthy, MBBS, MPH, Baylor Scott & White Health; William F. Fadel, PhD, Regenstrief Institute, IU Richard M. Fairbanks School of Public Health; Nancy Grisel, MPP, Intermountain Healthcare; Charlene McEvoy, M.D., MPH, HealthPartners Institute; Ned Lewis, MPH, Kaiser Permanente Northern California Division of Research; Michelle A. Barron, M.D., University of Colorado Anschutz Medical Campus; Juan Nanez, R.N., BSN, Paso del Norte Health Information Exchange (PHIX); Sarah E. Reese, PhD, Westat; Mufaddal Mamawala, MBBS, MPH, Baylor Scott & White Health; Nimish R. Valvi, DrPH, Regenstrief Institute; Julie Arndorfer, MPH, Intermountain Healthcare; Kristin Goddard, MPH, Kaiser Permanente Northern California Division of Research; Duck-Hye Yang, PhD, Westat; Bruce Fireman, M.A., Kaiser Permanente Northern California Division of Research; Sarah W. Ball, ScD, MPH, Westat; Ruth Link-Gelles, PhD, Centers for Disease Control and Prevention COVID-19 Response Team; Allison L. Naleway, PhD, Kaiser Permanente Northwest; and Mark W. Tenforde, M.D., PhD, Centers for Disease Control and Prevention COVID-19 Response Team.

About Brian E. Dixon, PhD, MPA 

In addition to his roles as interim director of the Regenstrief Institute’s Clem McDonald Center for Biomedical Informatics and director of public health informatics for Regenstrief Institute and Indiana University Richard M. Fairbanks School of Public Health, Brian E. Dixon, PhD, MPA is a professor of epidemiology at the Fairbanks School of Public Health. He is also an affiliate scientist at the U.S. Department of Veterans Affairs Health Services Research and Development Center for Health Information and Communication, Richard L. Roudebush VA Medical Center. 

About Shaun Grannis, M.D., M.S.
In addition to his role as the vice president for data and analytics at Regenstrief Institute, Shaun Grannis, M.D., M.S., is the Regenstrief Professor of Medical Informatics and a professor of family medicine at Indiana University School of Medicine.

About Regenstrief Institute
Founded in 1969 in Indianapolis, the Regenstrief Institute is a local, national and global leader dedicated to a world where better information empowers people to end disease and realize true health. A key research partner to Indiana University, Regenstrief and its research scientists are responsible for a growing number of major healthcare innovations and studies. Examples range from the development of global health information technology standards that enable the use and interoperability of electronic health records to improving patient-physician communications, to creating models of care that inform practice and improve the lives of patients around the globe.

Sam Regenstrief, a nationally successful entrepreneur from Connersville, Indiana, founded the institute with the goal of making healthcare more efficient and accessible for everyone. His vision continues to guide the institute’s research mission.

About the Richard M. Fairbanks School of Public Health 

Located on the IUPUI and Fort Wayne campuses, the Richard M. Fairbanks School of Public Health is committed to advancing the public’s health and well-being through education, innovation and leadership. The Fairbanks School of Public Health is known for its expertise in biostatistics, epidemiology, cancer research, community health, environmental public health, global health, health policy and health services administration.

About IU School of Medicine

IU School of Medicine is the largest medical school in the U.S. and is annually ranked among the top medical schools in the nation by U.S. News & World Report. The school offers high-quality medical education, access to leading medical research and rich campus life in nine Indiana cities, including rural and urban locations consistently recognized for livability.