The findings came in a new comprehensive analysis of virus cases in mainland China. Taking into account estimates of the number of cases that may not have been clinically confirmed -- that is, mild or asymptomatic infections -- the data showed the hospitalisation rate of patients in their fifties was 8.2 percent. The study, published in The Lancet Infectious Diseases journal, estimated that the mortality rate from confirmed COVID-19 cases in mainland China was 1.38 percent.