Does Blood type Affect My Risk of Covid-19
Patients with COVID-19 infection have a dramatic variability in presentation, from being asymptomatic to presenting with rapidly declining respiratory discomfort and even sudden death.
While it is understood that older aged individuals and those with greater medical issues have a higher risk according to the U.S. Centers for Disease Control and Prevention. – there are unfortunately also too many cases of otherwise healthy younger adults with severe disease who also can suffer death. As such it is important to understand what other risk factors affect outcomes.
According to a European study from the genetic analysis of 1,900 patients with severe cases of coronavirus published in the New England Journal of Medicine, people with blood Type O, the most common blood type, are 35% less likely to get coronavirus while people who have blood Type A were “associated with” a 45% “higher risk of acquiring COVID-19”.
It is already understood that human blood group antigens can increase or decrease susceptibility to many infections by serving as receptors for bacteria, parasites, and viruses while several blood groups can modify the patients immune response to infection. For example in the case of populations living in endemic areas with malaria some genetic varieties of blood types show greater resistance to the disease.
Roy Silverstein, former president the American Society of Hematology and Chairman of the Department of Medicine at the Medical College of Wisconsin warns however that ‘Those who are not type A should not interpret this study to mean that they can let their guard down. Similarly, the data are not yet convincing enough to recommend that those with type A need to do even more than what is recommended.’
Other studies also suggest a statistical correlation between non-O blood type and a higher rate of infection or more severe disease.
While data is limited still – a Chinese preprint study that looked at over 2000 COVID-19 positive individuals reported that there was a higher infection and death rate in people with type A blood than the general population while conversely fewer individuals with Type O blood were infected than would have been expected statistically.
Additionally while it is still very early, preliminary data from 23andMe’s ongoing genetic study of COVID-19 in the 750,000 who participated in their study also points to differences in the susceptibility to the virus based on ABO blood type. Specifically the data suggests that O blood type appears to be protective against the virus by as much as 18% when compared to all other blood types.
Research is ongoing.