London: A simple blood test may predict the risk of severe COVID-19 infection, say scientists who have identified a particular molecular signature in the blood that increases the chances of hospitalisation by 5 to 10 times in people infected by the novel coronavirus.The test can be used to identify people who'll need special precautions to avoid infection and prioritise those in most need of the COVID-19 vaccine, according to the scientists at Nightingale Health, a biotechnology company in Helsinki, Finland.Identification of healthy people at high risk for severe COVID-19 is a global health priority, they said.The researchers investigated whether blood biomarkers measured by high-throughput metabolomics could be predictive of severe.