Disease progression in patients with COVID-19: a retrospective cohort study in China.

To evaluate the clinical features of disease progression among patients with COVID-19 to help early identification of patients at high risk. This was a retrospective, multi-centre cohort study. From 10 January to 29 February 2020, all cases diagnosed with COVID-19 at 24 hospitals (with complete medical records) in Jiangsu Province, China were recruited. The primary outcome was deterioration in condition, i.e., the dramatic progression from asymptomatic or mild or moderate status into severe or critically ill status during 14 days´ follow-up. Of the 625 patients in Jiangsu, none died; 597 patients were asymptomatic or had mild or moderate disease on admission, of whom 36 (6%) experienced disease deterioration to become severe or critically ill. Disease deterioration to severe or critically ill status was associated with age, pulmonary opacity score, lymphocyte count on admission and exposure to the pandemic centre in Wuhan.