Clinical and CT features of early-stage patients with COVID-19: a retrospective analysis of imported cases in Shanghai, China

Since December 2019, some patients with novel corona virus infectious disease (COVID-19) emerged in Wuhan, Hubei, China [1]. The pathogen analysis discovered a new type of coronavirus from infected airway epithelial cells [2] and named as sever acute respiratory syndrome-related coronavirus 2 (SARS-CoV-2) [3]. At the time of Chinese people were heading home for celebrating the Spring Festival, many latent cases left Wuhan, which led to the emergence of imported COVID-19 cases across the mainland of China and some other countries [4, 5]. Shanghai is one of the major cities with imported cases [4, 5].