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Two new studies co-authored by HealthPartners Institute confirm COVID-19 vaccines are highly protective, even against Delta variant

As COVID-19 hospitalization rates climb, new data in CDC’s Morbidity and Mortality Weekly Report and the New England Journal of Medicine highlight preventive power of vaccines

September 10, 2021

Bloomington, Minn. – COVID-19 vaccines appear to protect recipients against the now dominant Delta variant of the novel coronavirus, according to new data published in the Centers for Disease Control and Prevention’s Morbidity and Mortality Weekly Report.

Researchers looked at more than 30,000 urgent care visits, emergency department visits and hospital admissions during June and July after the Delta variant was widely circulating in the United States. They determined that the effectiveness of COVID-19 vaccines against COVID-19 hospitalizations and emergency and urgent care encounters remained similar to the vaccine effectiveness prior to Delta variant predominance.

“People have been speculating about how effective COVID-19 vaccines are against the Delta variant and we now have evidence that suggests these vaccines are still very protective,” said Malini DeSilva, MD, investigator with HealthPartners Institute and co-author on the study. “These vaccines remain the best way to prevent severe COVID-19, protect yourself, loved ones and community.”

This data builds on other recent research that validates overall vaccine effectiveness. On Wednesday, September 8, 2021, the New England Journal of Medicine published a similar study, also authored by the same group of researchers, looking at vaccine effectiveness from January to June of this year when the Alpha variant was still dominant. It suggested vaccines remain effective against the original strain of COVID-19.

About HealthPartners Institute

HealthPartners Institute is part of HealthPartners, the largest consumer-governed, non-profit health care organization in the nation with a mission to improve health and well-being in partnership with members, patients and the community. HealthPartners Institute supports this mission through research, education and practice. The Institute annually conducts 400+ research studies and trains 700+ medical residents and fellows and 1,200+ medical and advanced practice students. Its integration with HealthPartners’ hospitals, clinics and health plan strengthens the Institute’s ability to discover and develop evidence-based solutions and translate them into practice. Based in Minneapolis, the Institute’s work impacts care, health and well-being across the region and nation as well as internationally. Visit for more information.

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