As per the observations made according to these data, they concluded that people who had blood type O were less vulnerable whereas people with A and AB were more at risk.
Scientists have been investigating a potential link between blood type and vulnerability to Covid-19 for many months, and this latest evidence supports previous findings.
The scientists collected data from the Danish health registry data of over 473,000 people who had tested positive for the novel coronavirus. Researchers in Denmark find fewer coronavirus patients have O blood compared to those with A, B, and AB blood. "It is very important to consider the proper control group because blood type prevalence may vary considerably in different ethnic groups and different countries", said study author Torben Barington from the University of Southern Denmark.
A preprint study published in March this year suggested that people with blood type A have a higher risk of acquiring Covid-19 compared with non-A blood groups, while another study published in June found that blood type O seemed to be more resistant against Covid-19 infection.
People with blood group O positive can donate blood only to people with positive blood groups like A+, B+, O+, AB+. A small handful of other studies have also indicated that people with blood type O appear to be less likely than any other blood type to test positive for Covid-19 and less likely to fall seriously sick. Further investigations on the mechanism of the different susceptibility to COVID-19 between blood group A and O individuals are needed and regardless of your blood type, you need to follow public health recommendations.
The other study included 95 critically ill COVID-19 patients hospitalized in Canada.
Interestingly, blood groups, A and AB were also associated with complications post-hospitalization, such as myocarditis, lung injury and renal damage.
Patients with blood types A and AB did not have longer hospital stays than those with types O or B, but they did experience longer intensive care unit stays, which may signal greater COVID-19 severity. They found that patients with blood groups A or AB were more likely to need mechanical ventilation, with 84 percent of A or AB patients requiring mechanical ventilation compared to 61 percent of O or B patients. Another study in April (pre-print and awaiting peer-review) found that among 1,559 coronavirus patients in New York City, a lower proportion than would be expected had Type O blood.