Research is focusing on the idea that people with type O blood may have a slight advantage during this pandemic.
Two studies published this week suggest that people with type O have a lower risk of contracting the coronavirus, as well as a reduced chance of becoming seriously ill if they become infected.
One of the new studies specifically found that COVID-19 patients with type O or B blood spent less time in an intensive care unit than their counterparts with type A or AB. They were also less likely to require ventilation and less likely to experience kidney failure.
These new findings echo similar findings about type O blood seen in previous research, creating a clearer picture of a particular coronavirus risk factor.
Patients with type O or B blood had less severe COVID-1
Both new studies appeared in the journal Wednesday Blood advances. One examined 95 critically ill COVID-19 patients in hospitals in Vancouver, Canada, between February and April.
They found that patients with type O or B blood spent, on average, 4.5 fewer days in the ICU than those with type A or AB blood. The latter group remained, on average, 13.5 days in intensive care. However, the researchers found no link between blood group and the length of each patient’s total hospital stay.
However, they found that only 61% of patients with type O or B blood needed a ventilator, compared with 84% of patients with type A or AB.
Patients with type A or AB, meanwhile, were also more likely to need dialysis, a procedure that helps the kidneys filter toxins from the blood.
“Patients in these two blood groups may have a greater risk of organ dysfunction or failure due to COVID-19 than people with blood groups O or B,” the study authors concluded.
A June study found a similar link: patients in Italy and Spain with type O blood had a 50% reduced risk of severe coronavirus infection (meaning they needed intubation or supplemental oxygen) compared to patients with other blood types.
People with type O blood had a “reduced susceptibility” to infections
The second new study found that people with type O blood may have a lower risk of contracting the coronavirus in the first place than people with other blood types.
The team looked at nearly half a million people in the Netherlands who were tested for COVID-19 between the end of February and the end of July. Of the approximately 4,600 people who tested positive and reported their blood type, 38.4% had type O blood.
It is less than the prevalence of type O in a population of 2.2 million Danes, 41.7 percent, so the researchers determined that people with type O blood disproportionately avoided infection.
“Blood group O is significantly associated with reduced susceptibility,” the authors wrote.
Other studies have found a similar link between blood group and COVID-19 risk
In general, your blood type depends on the presence or absence of proteins called A and B antigens on the surface of red blood cells, a genetic trait inherited from your parents. People with O blood have neither antigen. It is the most common blood group – about 48 percent of Americans have type O blood, according to the Oklahoma Blood Institute.
The new studies on blood group and coronavirus risk are in line with previous research on the subject. A study published in July found that people with type O were less likely to test positive for COVID-19 than those with other blood types. An April study (though it has yet to be peer-reviewed) also found that among 1,559 coronavirus patients in New York City, fewer than expected had type O blood.
And in March, a study of more than 2,100 coronavirus patients in the Chinese cities of Wuhan and Shenzhen also found that people with type O blood had a lower risk of infection.
Previous research has also suggested that people with type O blood were less susceptible to SARS, which shares 80% of its genetic code with the new coronavirus. A 2005 study in Hong Kong found that most people infected with SARS had non-O blood types.
Despite this growing body of evidence, however, Mypinder Sekhon, a co-author of the Vancouver study, said the link is still weak.
“I don’t think this replaces other severity risk factors like age and comorbidities and so on,” he told CNN, adding, “if one is in blood type A, they don’t need to start panicking. . And if you are blood type O, you are not free to go to pubs and bars. “
This article was originally published by Business Insider.
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