The Epidemiological Characteristics of an Outbreak of 2019 Novel Coronavirus Diseases (COVID-19) — China, 2020

Background: An outbreak of 2019 novel coronavirus diseases (COVID-19) in Wuhan, Hubei Province, China has spread quickly nationwide. Here, we report results of a descriptive, exploratory analysis of all cases diagnosed as of February 11, 2020. Methods: All COVID-19 cases reported through February 11, 2020 were extracted from China’s Infectious Disease Information System. Analyses included the following: 1) summary of patient characteristics; 2) examination of age distributions and sex ratios; 3) calculation of case fatality and mortality rates; 4) geo-temporal analysis of viral spread; 5) epidemiological curve construction; and 6) subgroup analysis. Results: A total of 72,314 patient records—44,672 (61.8 % ) confirmed cases, 16,186 (22.4 % ) suspected cases, 10,567 (14.6 % ) clinically diagnosed cases (Hubei Province only), and 889 asymptomatic cases (1.2 % )—contributed data for the analysis. Among confirmed cases, most were aged 30–79 years (86.6 % ), diagnosed in Hubei (74.7 % ), and considered mild (80.9 % ). A total of 1,023 deaths occurred among confirmed cases for an overall case fatality rate of 2.3 % . The COVID-19