Pattern of COVID-19 in Sichuan province, China: A descriptive epidemiological analysis

This study described the epidemiology of 487 confirmed coronavirus disease 2019 (COVID-19) cases in Sichuan province of China, and aimed to provide epidemiological evidence to support public health decision making. Epidemiological information of 487 COVID-19 cases were collected from the official websites of 21 districts (including 18 cities, 3 autonomous prefecture) health commissions within Sichuan between 21(st) of January 2020 to 17(th) of April 2020. We focus on the single-day diagnosis, demographics (gender and age), regional distribution, incubation period and symptoms. The number of single-day confirmed COVID-19 cases reach a peak on January 29 (33 cases), and then decreased. Chengdu (121 cases), Dazhou (39 cases) Nanchong (37 cases) and Ganzi Tibetan Autonomous Prefecture (78 cases) contributed 275 cases (56.5% of the total cases) of Sichuan province. The median age of patients was 44.0 years old and 52.6% were male. The history of living in or visiting Hubei, close contact, imported and unknown were 170 cases (34.9%), 136 cases (27.9%), 21 cases (4.3%) and 160 cases (32.9%) respectively. The interval from the onset of initial symptoms to laboratory diagnosis was 4.0 days in local cases, while that of imported cases was 4.5 days. The most common symptoms of illness onset were fever (71.9%) and cough (35.9%). The growth rate of COVID-19 in Sichuan has significantly decreased. New infected cases have shifted from the living in or visiting Wuhan and close contact to imported. It is necessary to closely monitor the physical condition of imported cases.