[The epidemiological characteristics of an outbreak of 2019 novel coronavirus diseases (COVID-19) in China]

Zhonghua Liu Xing Bing Xue Za Zhi. 2020 Feb 10;41(2):145-151. doi: 10.3760/cma.j.issn.0254-6450.2020.02.003.
[Article in Chinese]

Abstract

Objective: An outbreak of 2019 novel coronavirus diseases (COVID-19) in Wuhan, 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: 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, 10567 (14.6%) clinical diagnosed cases (Hubei 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/mild pneumonia (80.9%). A total of 1 023 deaths occurred among confirmed cases for an overall case-fatality rate of 2.3%. The COVID-19 spread outward from Hubei sometime after December 2019 and by February 11, 2020, 1 386 counties across all 31 provinces were affected. The epidemic curve of onset of symptoms peaked in January 23-26, then began to decline leading up to February 11. A total of 1 716 health workers have become infected and 5 have died (0.3%). Conclusions: The COVID-19 epidemic has spread very quickly. It only took 30 days to expand from Hubei to the rest of Mainland China. With many people returning from a long holiday, China needs to prepare for the possible rebound of the epidemic.

目的: 新型冠状病毒肺炎在武汉暴发流行以来,已在全国范围内蔓延。对截至2020年2月11日中国内地报告所有病例的流行病学特征进行描述和分析。 方法: 选取截至2020年2月11日中国内地传染病报告信息系统中上报所有新型冠状病毒肺炎病例。分析包括:①患者特征;②病死率;③年龄分布和性别比例;④疾病传播的时空特点;⑤所有病例、湖北省以外病例和医务人员病例的流行病学曲线。 结果: 中国内地共报告72 314例病例,其中确诊病例44 672例(61.8%),疑似病例16 186例(22.4%),临床诊断病例10 567例(14.6%),无症状感染者889例(1.2%)。在确诊病例中,大多数年龄在30~79岁(86.6%),湖北省(74.7%),轻/中症病例为主(80.9%)。确诊病例中,死亡1 023例,粗病死率为2.3%。个案调查结果提示,疫情在2019年12月从湖北向外传播,截至2020年2月11日,全国31个省的1 386个县区受到了影响。流行曲线显示在1月23-26日达到峰值,并且观察到发病数下降趋势。截至2月11日,共有1 716名医务工作者感染,其中5人死亡,粗病死率为0.3%结论: 新型冠状病毒肺炎传播流行迅速,从首次报告病例日后30 d蔓延至31个省(区/市),疫情在1月24-26日达到首个流行峰,2月1日出现单日发病异常高值,而后逐渐下降。随着人们返回工作岗位,需积极应对可能出现的疫情反弹。.

Keywords: 2019 Novel Coronavirus; Epidemiological characteristics; Outbreak.

MeSH terms

  • Adult
  • Aged
  • Asymptomatic Diseases / epidemiology*
  • Betacoronavirus
  • COVID-19
  • China / epidemiology
  • Coronavirus Infections / diagnosis*
  • Coronavirus Infections / mortality
  • Coronavirus*
  • Disease Outbreaks
  • Humans
  • Middle Aged
  • Mortality* / trends
  • Pandemics*
  • Pneumonia, Viral / diagnosis*
  • Pneumonia, Viral / mortality
  • SARS-CoV-2