People with blood type O are less likely to be infected of Covid: the study

Both a Danish and a Canadian study found that Blood Type A, B and AB are more likely to be infected of Covid.

While the world awaits a vaccine, two independent studies show that people with blood type O are less likely to catch Covid than people with A, B, and AB blood types. Their risk of severe complications such as organ failure, and even death, is also reduced. However, individuals with blood types A and AB are most vulnerable, according to new research.

The findings from two independent studies shed fresh light on why the virus is deadly for some while others are not even aware they have had it.

The Danish study

One team compared Danish health registry data of over 473,000 individuals tested for Covid to a control group of more than 2.2 million from the general population. There were fewer positive results among those with blood type O and more people infected with A, B, and AB. Rates of infection were similar in these three groups. The trends remained after the researchers took into account ethnicity which affects blood group distributions.

Lead author Dr. Torben Barington, of Odense University Hospital, said: “It is very important to consider the proper control group because blood type prevalence may vary considerably in different ethnic groups and in different countries.

He also added that they have the advantage of a strong control group. It is because Denmark is a small, ethnically homogenous country with a public health system and a central registry for lab data.

The Canadian study

A second study of 95 critically ill Covid patients in hospital in Vancouver found the A and AB blood types were at higher risk of severe symptoms than those with O or B. They were more likely to require mechanical ventilation. They had greater rates of lung injury from the virus and dialysis for kidney failure. It suggests these two blood groups have an increased risk of organ dysfunction or failure due to infection of the virus.

The study also showed that people with blood types A and AB remained in the intensive care unit (ICU) for longer on average. Lead author Dr. Mypinder Sekhon, of the University of British Columbia, said, “The unique part of our study is our focus on the severity effect of blood type on Covid. We observed this lung and kidney damage, and in future studies, we will want to tease out the effect of blood group and Covid on other vital organs.”

Those study in line with a study in China. They found that 206 who died, 85 had blood type A equivalent to 41 percent of all deaths. The death toll from Covid has recently spoken of one million deads.