People with blood type A are at a significantly higher risk of developing severe Covid-19, according to a study that found genetic factors that may explain why some people are so much more affected by the virus.
The research, accepted for publication in a peer-reviewed journal, examined the genomes of more than 1,600 people hospitalized with Covid-19 who needed respiratory help and compared them to those who had not contracted the disease.
Those with blood group A appeared to be up to 50% more likely to need oxygen or a ventilator. About 42% of Britons have blood group A.
The finding is in addition to other evidence in China suggesting a blood type, which