ID 原文 译文
49419 由于新冠肺炎病毒是一种新发现的病原体，人群普遍缺乏免疫力。 As COVID-19 is a newly identified pathogen, there is no known pre-existing immunity in humans.
49420 根据目前在中国观察到的流行病学特征，几乎人人易感，尽管可能存在易感性增加的危险因素，但还需要进一步研究，明确感染后是否具有免疫力。 Based on the epidemiologic characteristics observed so far in China, everyone is assumed to be susceptible, although there may be risk factors increasing susceptibility to infection. This requires further study, as well as to know whether there is neutralising immunity after infection.
49421 (三）传播动力学 The transmission dynamics
49422 根据图2和3以及根据我们在国家和省/市级的联合考察的观察结果，总结和解释了新冠肺炎迄今为止的传播动力学。 Inferring from Figures 2 and 3, and based on our observations at the national and provincial/municipal levels during the Joint Mission, we summarize and interpret the transmission dynamics of COVID-19 thus far.
49423 任何疫情暴发的传播动力学本质上都是与具体情境有关，了解这点很重要。 It is important to note that transmission dynamics of any outbreak are inherently contextual.
49424 对于新冠肺炎，我们分析了在流行增长期到控制措施实施后的时间段内观察到的四种主要的传播模式，并突出了对儿童传播的了解，如下所示： For COVID-19, we observe four major types of transmission dynamics during the epidemic growth phase and in the post-control period, and highlight what is known about transmission in children, as follows:
49425 武汉传播模式 Transmission in Wuhan
49426 在武汉发现的早期病例被认为是通过动物传染到人的途径感染，因为许多人报告有华南海鲜批发市场暴露史。 Early cases identified in Wuhan are believed to be have acquired infection from a zoonotic source as many reported visiting or working in the Huanan Wholesale Seafood Market.
49427 截至2月25日，尚未查明动物来源。 As of 25 February, an animal source has not yet been identified.
49428 在疫情早期的某个时点，部分病例间产生了人际传播，导致随后在一系列控制措施实施前发生了社区暴发并首先在武汉扩散开，再随着大规模人口流动，从武汉进一步辐射到湖北省和中国其他大部分地区，从而解释了高达2-2.5的传播系数（R0值）。 At some point early in the outbreak, some cases generated human-to-human transmission chains that seeded the subsequent community outbreak prior to the implementation of the comprehensive control measures that were rolled out in Wuhan. The dynamics likely approximated mass action and radiated from Wuhan to other parts of Hubei province and China, which explains a relatively high R0 of 2-2.5.