Epidemic Characteristics of COVID-19 in Four Chinese Cities.

In December 2019, there was an outbreak of coronavirus disease 2019 (COVID-19) in Wuhan, China. To date, the number of patients in China has risen to 31,000. We collected patient data from 4 Chinese cities (Hefei, Hangzhou, Wenzhou, and Shenzhen) and described epidemiologic characteristics. As of February 6, 2020, we have extracted data from 950 patients from the 4 cities, including 477 (50.21%) men and 473 (49.79%) women. The age (mean ± standard deviation) was 45.64 ±15.59 years. Before contracting COVID-19, 299 (31.47%) patients had come in contact with Wuhan residents or patients diagnosed with COVID-19, while 138 (14.53%) patients had severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection from an unknown source. Most COVID-19 patients in the 4 cities were from Wuhan originally and had spread the infection locally. Therefore, the initial stage of SARS-CoV-2 transmission in cities outside of Wuhan were mainly input. Cutting off the input and controlling the community communication could reduce local incidence.