Our study had several limitations. First, because COVID-19 is a novel disease and lacks a series and long-term CT data, we can analyze only the existing information in a retrospective analysis. Moreover, the time of chest CT examination after symptom onset was inconsistent, so it was difficult to summarize the CT appearances that could reflect the whole course of the disease. Second, the sample size in our study was relatively small, and there may be deviation in the comparison of the results of CT findings. Third, most of our cases were imported cases and some were secondary cases. Further research is needed to observe whether virus variation exists in the process of infection and whether virus variation will produce different in CT manifestations. Finally, there was no histopathological evidence from deceased patients.