How Does Blood Type Affect Susceptibility To COVID-19?

by Kroger Health Staff

Last Updated: July 9, 2020

With researchers working diligently to understand COVID-19, new information is constantly emerging. While most people who contract COVID-19 experience little to no symptoms, certain factors may elevate this risk. Initial findings from a European study discovered a potential link between blood types (A, O, B, and AB) and risk from COVID-19. Below are three takeaways based on the current research.
  1. Early studies indicate people with Type A blood are at higher risk.
    Scientists compared the genes of 1,610 patients across Italy and Spain and found a potential link to blood type that may indicate who is likely to get extremely ill from COVID-19. Initial findings indicate those with Type A blood are at increased risk for respiratory failure, which is a critical driver of COVID-19 mortality. The study findings, which are pending peer review, were published in the New England Journal of Medicine. Furthermore, past research indicates that people with blood types A and B may be at higher risk of developing dangerous blood clots. Blood clotting is a major complication found in many severe COVID-19 infections, according to the National Institutes of Health (NIH).
  2. Early studies indicate people with Type O blood are more protected.
    The same European study also found that there was a protective effect for people with Type O blood, which account for roughly 44% of the US population, according to the Stanford University Blood Center. People with Type O blood were discovered to have about 50 percent reduced risk of severe COVID-19, which entails a greater need for oxygen support or a ventilator. This European study confirms an earlier Chinese study, which also linked Type O blood with reduced risk. A similar finding was established with the SARS coronavirus, a genetic cousin to COVID-19, where people with Type O blood were less likely to become infected.
  3. More research is underway, so people with all blood types should remain vigilant.
    While the findings are statistically significant, these initial studies advise against using the research to guide clinical practices yet. The higher risk found with Type A blood has not been validated enough to warrant modified precautionary guidelines among the general public, and the research conducted is still pending peer review and follow-up studies. However, these blood type findings can be potentially useful in the search for effective COVID-19 treatments and vaccines.

Researchers and health professionals are working together to save lives by analyzing the risk factors and the resulting impacts of COVID-19. Each day, we are closer to fully understanding how the virus operates and impacts the body, how it is transmitted, and the precautions to take to prevent further spread.

Disclaimer: The information in this story is accurate as of its publication. However, the situation surrounding COVID-19 is ever-evolving. We are working to keep our stories up-to-date as changes occur, but we also encourage everyone to check news and recommendations from the CDC, WHO, and their local authorities.