People with blood type A may be more vulnerable to infection by 

the new coronavirus

, while those with type O seem more resistant, according to a preliminary study of patients in China who contracted the disease known as Covid-19.

Medical researchers in China took blood group patterns of more than 2,000 patients infected with the virus in Wuhan and Shenzhen and compared them to local healthy populations. They found that blood type A patients showed a higher rate of infection and they tended to develop more severe symptoms.

While the researchers said the study was preliminary and more work was needed, they did urge governments and medical facilities to consider blood type differences when planning mitigation measures or treating patients with the virus, known as Sars-CoV-2.