February 28, 2025
It is safe to receive blood during a medical procedure from someone who has been vaccinated against COVID-19, a new Kaiser Permanente study confirms.
Nareg Roubinian, MD
“Some patient advocacy groups have stated that it is not safe to receive a blood transfusion from blood donors who have been vaccinated against COVID-19,” said lead author Nareg Roubinian, MD, an adjunct investigator at the Kaiser Permanente Northern California Division of Research and a critical care physician with The Permanente Medical Group. “Our study is the first to link specific SARS-CoV-2 antibody data from blood donors with the patients who received their blood, and we found no evidence that patients who had received blood from a donor who had been vaccinated was affected in a negative way by that blood product. In fact, in many cases, the blood may have helped save their lives.”
The retrospective study, published in Transfusion, is the first to directly link specifics about the vaccination status of a blood donor and the SARS-CoV-2 antibodies found in their blood to the outcomes of recipients of plasma or platelet blood products.
The study included all hospitalized adult, non-obstetric patients of Kaiser Permanente Northern California who received a plasma or platelet transfusion between June 2020 and March 2022, a time period when many blood donors were infected or vaccinated against SARS-CoV-2. None of the patients who received transfusions had COVID at the time they were admitted to the hospital or within the past month.
During the study period, there were 8,715 hospitalizations of 7,773 patients who received plasma or platelet transfusions. Among these hospitalizations, 79.6% (6,939) were emergency admissions and 36.9% (3,215) were surgical procedures.
Of the 15,167 donated plasma units used for these patients, 4,993 were from vaccinated donors and 1,106 were from previously infected donors. Of the 19,295 transfused platelet units, 8,530 were from vaccinated donors and 1,368 were from previously infected donors.
Among the 7,773 patients, there were 251 blood clots, 700 hospitalizations for patients who needed increased assistance with breathing, and 1,443 deaths. The study found no association between the blood products donated by vaccinated or previously infected donors and the risk of these 3 outcomes known to occur after COVID-19 infection. This was true whether the donor had a history of COVID-19 and was vaccinated, or had a history of COVID-19 but was not vaccinated.
Keeping the blood supply safe
KP Northern California receives blood products from the American Red Cross and Vitalant. Between June 2020 through March 2022, both participated in universal SARS-CoV-2 screening of all blood donations as part of the CDC-funded Nationwide Blood Donor Serosurveillance (NBDS) study.
After COVID-19 vaccines began being administered in January 2021, additional antibody tests were more routinely used to identify which donors had evidence of a prior infection. All donors were also asked if they had received a COVID-19 vaccine and, if so, when. The collection of this data at the time of the blood donation made this study possible.
The authors noted that previous research provides additional reassurance on the safety of the nation’s blood supply. Studies have shown that components of COVID-19 vaccines do not remain in the bloodstream for prolonged periods after vaccination, making it unlikely they would be present in donated blood. In addition, antibodies produced in response to vaccination are similar or more robust than those generated by natural infection, and natural infection causes no harm during a blood transfusion.
“Our study supports the belief that the blood supply has been and is safe,” said Dr. Roubinian. “We hope our findings are reassuring to individuals who are worried about receiving a blood transfusion from someone who has been vaccinated against COVID-19.”
The study was supported by the National Heart, Lung, and Blood Institute.
Co-authors include Vincent X. Liu, MD, MS, and John Greene, MA, of the Kaiser Permanente Division of Research; Bryan R Spencer, PhD, and Paula Saa, PhD, of the American Red Cross; Marjorie Bravo, MD, of Vitalant; Roberta Bruhn, PhD, Mars Stone, PhD, Brian Custer, PhD, MPH, Philip J Norris, MD, and Michael P. Busch, MD, PhD, of the Vitalant Research Institute; and Steve Kleinman, MD, of the University of British Columbia, for the NHLBI Recipient Epidemiology and Donor Evaluation Study-IV-P (REDS-IV).
This article originally appeared on Division of Research Spotlight.
