Could your blood type protect you from the coronavirus? Make you vulnerable? Studies say maybe.

Your new blood type can determine how susceptible you are to getting a severe case of COVID-19, new studies show.

Three studies indicate that people with type O blood have at least some protection against the coronavirus, while people with type A tend to contract the virus more frequently and develop more severe cases.

The studies are limited in scope, making it too early to say whether their findings have uncovered a conclusive link between blood type and disease outcomes. Other factors such as age and pre-existing conditions have a stronger history of predicting a person’s vulnerability.

And the findings don’t mean that people with type O blood should let their guard down.

“These studies add to our knowledge of those who will have better results and those who will have less successful results,” said Sandra Adams, a professor of biology at Montclair State University, who reviewed two of the studies. “I wouldn’t tell people with type O blood to party and forget about all the other factors.”

A study published in the New England Journal of Medicine last week looked at the blood types of 1,980 patients in European countries.

The researchers found that the Type O blood group is associated with a lower risk of acquiring COVID-19 than the non-O blood groups. The Type A blood group was associated with a higher risk than the non-A groups.

Two other studies, which have not yet been peer-reviewed, show similar findings.

One looked at 2,173 Chinese patients in Wuhan and Shenzhen and discovered potential benefits for those with type O blood. But the study, published in late March, said it was “premature” for its findings to guide clinical practice. However, “they should encourage further investigation of the relationship between ABO blood group and COVID-19 susceptibility,” the study said.

The other study, the only one of the three involving US patients, found that people with type A blood were 33% more likely to test positive for COVID-19 than others. The study, which involved 1,559 New York patients, also found that those with type O blood were still the least likely to test positive.

Type O is the most common blood type, according to the American Red Cross.

Studies have linked blood type to results from other viruses, and found that anti-A antibodies in type O blood have been helpful, Adams said.

But the studies probably won’t lead to an immediate cure or a single treatment for COVID-19, he said. Instead, they could inform more about the approaches of doctors and researchers to understand it.

“Because there are so many variables, I think this should be added to the list of factors we consider” in treating the virus, Adams said.

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Amanda Hoover can be contacted at [email protected]. Follow her on Twitter @amandahoovernj.