The O- blood group had the lowest probability the SARS-Cov-2 infection, while the B+ blood team had the highest probability.

Patients with form O and rhesus an adverse (Rh-) blood teams may have a reduced risk of serious acute respiratory tract syndrome coronavirus 2 (SARS-CoV-2) infection and severe coronavirus an illness 2019 (COVID-19) illness, follow to a study released in the Annals of interior Medicine.

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Investigators carried out a population-based, retrospective cohort study of 225,556 patient who had their ABO blood group assessed in between January 2007 and also December 2019, and also subsequently tested because that SARS-CoV-2 between January 15 and also June 30, 2020. The mean age was 53.8 years and also 29% were men. Common comorbidities contained preexisting cardiac condition (13-15%), chronic kidney condition (11%), anemia (21%), cancer (27-29%), dementia or frailty (33-38%), diabetes mellitus (21%), asthma (18-21%), and also chronic hypertension (39-41%).

The study’s main outcome was SARS-CoV-2 infection. The an additional outcome was severe COVID-19 condition or death. Readjusted relative threats (aRRs) and absolute risk differences (ARDs) were adjusted for demography characteristics and also comorbidities. Because that the major outcome, analyses were more stratified by patients age younger 보다 70 years vs 70 year or older.

The O- blood team had a 2.1% opportunity of acquiring SARS-CoV-2 infection (95% CI, 1.8-2.3%), the shortest unadjusted probability of every blood groups. The aRR for SARS-CoV-2 epidemic in the O blood group was 0.88 (95% CI, 0.84-0.92) vs all various other blood groups, and the ARD to be -3.9 every 1,000 (95% CI, -5.4 come -2.5). Comparatively, the greatest unadjusted probability of SARS-CoV-2 infection remained in the B+ blood group (4.2%; 95% CI, 4.0-4.5%). Results likewise indicated the aRR for SARS-CoV-2 infection was greater in patient with ab blood type compared with kind A.

Rh- status seemed protective versus SARS-CoV-2 infection through an aRR the 0.79 (95% CI, 0.73-0.85) and also an ARD that -6.8 per 1,000 (95% CI, -8.9 come -4.7). The O- blood group additionally seemed protective, through an aRR that 0.74 (95% CI, 0.66-0.83) and an ARD that -8.2 per 1,000 (95% CI, -10.8 come -5.3). The relative protective results of O, Rh-, and O- blood teams were greatest in patient younger than period 70.

Secondary result results indicated that kind O blood group had an aRR that 0.87 (95% CI, 0.78-0.97) for significant COVID-19 illness and also death versus all other blood groups and Rh- status had actually an aRR of 0.82 (95% CI, 0.68–0.96) compared to Rh+ status. The O- blood group did not appear protective versus severe COVID-19 illness and death (aRR, 0.84; 95% CI, 0.64-1.07) compared with various other blood groups.

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“Studies the the accuracy of serologic tests for anti-SARS-CoV-2 immunoglobulins may assess whether over there is sport in antibody titers by ABO and also Rh status,” the writer noted. “Furthermore, amongst ongoing clinical trials of immunotherapy using convalescent plasma or the SARS-CoV-2 vaccines, the interaction in between participant blood groups and also therapeutic efficacy can be measured.”

Investigators also suggested further research on how ABO status may moderate venous thromboembolism occurrence, a recognized complication the COVID-19, since blood team O patients have actually been linked with a lessened risk that venous thromboembolism in former research.


Ray JG, Schull MJ, Vermuelen MJ, Park A. Association between ABO and also Rh blood groups and also SARS-CoV-2 epidemic or major COVID-19 illness. Ann Intern Med. Released online November 24, 2020. Doi:10.7326/M20-4511