As COVID-19 cases continue to rise in the United Kingdom, more people will suffer "debilitating" long-term after-effects of a related infection, academics have warned.
While no significant difference in the rate of infection was found between blood groups "A", "AB", and "B" types, the study did suggest that the first two are associated with an increased risk of severe clinical outcomes of the infection, the agency said in its report. Around 42 percent of the Danish population has blood type O and another 42 percent have blood type A. Despite equal representation, fewer people with blood type O caught Covid-19; just 38 percent of the people who tested positive were blood type O, while 44 percent were blood type A. Similarly, people with blood type B and AB also received more positive Covid-19 results than expected. Infection rates were similar among people with types A, B and AB blood. 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.
Also, people with type A and AB did not require a longer duration of hospitalisation but did remain in the intensive care unit (ICU) for longer on average, compared to people with types O or B, indicating a more severe form of COVID-19.
The researchers also wrote that their study's findings are congruent with a recent study of 1 980 Covid-19 patients that also demonstrated a link between ABO blood type and disease severity.
This lends credence to the fact that people with blood type A, B and AB, may be more at risk of getting infected than those with blood type O.
"It is very important to consider the proper control group because blood type prevalence may vary considerably in different ethnic groups and different countries", says study author Torben Barington, MD, of Odense University Hospital in a press release. 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.
Meanwhile, the scientists noted in the study, "We observed dis lung and kidney damage, and in future studies, we will want to tease out the effect of blood group and COVID-19 on other vital organs".
In the Canadian study, they looked at the length of hospital stays for 95 people critically ill with the coronavirus. This means that it's not clear how the relationship between blood type and Covid-19 works and any link may be coincidental.
According to the American Red Cross, O-positive is the most common type of blood across all races.