People With Blood Type O May Be at a Lower Risk of COVID-19, Say Studies

They are also less likely to have severe outcomes, like being put on a ventilator or having to undergo dialysis for kidney failure, according to one of the studies.
October 15, 2020, 12:34pm
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After months of anxiety and stress about the virus that has taken over 2020 and our lives in 2020, researchers are claiming that COVID-19 might be not as vulnerable to one blood type.

According to two recent studies published in Blood Advances, people with blood type (or blood group) O may be less vulnerable to COVID-19 and are also less likely to get severely ill. However, experts say more research is needed to establish this firmly.

The research provides evidence that may play a role in a person's susceptibility to the infection and their chance of having a severe bout of the disease. The reasons for this link, however, are not clear yet. 

To arrive at these findings, Danish researchers studied a sample of 7,422 people who tested positive for coronavirus and it was found that only 38.4 percent were blood type O. On the other hand, 44 percent of people with the blood group A had tested positive. 

According to the study results, people with blood types A, B or AB are more likely to test positive for COVID-19 than people with blood type O. 

In another study conducted in Canada, the researchers found out that among 95 patients who were critically ill with COVID-19, those with blood type O required a median intensive care unit stay of 9 days. But people with A or AB blood stayed 13.5 days. Those with the O blood group were also less likely to have severe outcomes, like being put on a ventilator or having to undergo dialysis for kidney failure.

“As a clinician... it is at the back of my mind when I look at patients and stratify them. But in terms of a definitive marker we need repeated findings across many jurisdictions that show the same thing,” said Mypinder Sekhon, an intensive care physician at Vancouver General Hospital and an author of the Canadian study to CNN. “I don't think this supersedes other risk factors of severity like age and co-morbidities and so forth. If one is blood group A, you don't need to start panicking. And if you're blood group O, you're not free to go to the pubs and bars.”

Though there have been several theories about this, researchers are not sure what mechanism could explain the link between different blood groups and coronavirus. There was a study that had come out of China as early as March that found that people with Type A blood were at higher risk of the virus, though this wasn’t a peer-reviewed study. 

However, there have also been studies to prove otherwise. According to Harvard Medical School researchers at Massachusetts General Hospital, blood type is not associated with a severe worsening of symptoms in people who have tested positive for COVID-19. The new evidence however does offer more clues into the study of the virus.

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