Association Between ABO and Rh Blood Groups and SARS-CoV-2 Infection or Severe COVID-19 Illness

Study (n=225,556) reports O [aRR 0.88;95% CI,0.84-0.92; absolute risk difference [ARD], −3.9/1000 [CI,−5.4 to −2.5]) and Rh− (0.79;0.73-0.85;ARD −6.8 per 1000 [CI −8.9 to −4.7]) blood groups may be linked to slightly lower risk for SARS-CoV-2 infection & severe COVID-19 illness.

Annals of Internal Medicine