MRC Centre for Global Infectious Disease Analysis, School of Public Health, Imperial College London, London, UK.
The Abdul Latif Jameel Institute for Disease and Emergency Analytics (J-IDEA), School of Public Health, Imperial College London, London, UK.
Science. 2021 May 21;372(6544):815-821. doi: 10.1126/science.abh2644. Epub 2021 Apr 14.
Cases of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in Manaus, Brazil, resurged in late 2020 despite previously high levels of infection. Genome sequencing of viruses sampled in Manaus between November 2020 and January 2021 revealed the emergence and circulation of a novel SARS-CoV-2 variant of concern. Lineage P.1 acquired 17 mutations, including a trio in the spike protein (K417T, E484K, and N501Y) associated with increased binding to the human ACE2 (angiotensin-converting enzyme 2) receptor. Molecular clock analysis shows that P.1 emergence occurred around mid-November 2020 and was preceded by a period of faster molecular evolution. Using a two-category dynamical model that integrates genomic and mortality data, we estimate that P.1 may be 1.7- to 2.4-fold more transmissible and that previous (non-P.1) infection provides 54 to 79% of the protection against infection with P.1 that it provides against non-P.1 lineages. Enhanced global genomic surveillance of variants of concern, which may exhibit increased transmissibility and/or immune evasion, is critical to accelerate pandemic responsiveness.
尽管巴西玛瑙斯此前的感染水平很高,但 2020 年底,严重急性呼吸综合征冠状病毒 2(SARS-CoV-2)感染病例再次出现。2020 年 11 月至 2021 年 1 月期间对玛瑙斯采集的病毒进行基因组测序显示,一种新型的令人关注的 SARS-CoV-2 变异株出现并传播。谱系 P.1 获得了 17 个突变,包括刺突蛋白中的三个突变(K417T、E484K 和 N501Y),与增加与人类 ACE2(血管紧张素转换酶 2)受体的结合有关。分子钟分析显示,P.1 的出现发生在 11 月中旬左右,之前经历了一个更快的分子进化时期。使用整合基因组和死亡率数据的两类别动力学模型,我们估计 P.1 的传播性可能高出 1.7-2.4 倍,并且之前(非 P.1)感染对 P.1 感染的保护作用比其对非 P.1 谱系的保护作用高 54-79%。加强对可能表现出更高传播性和/或免疫逃避的关注变异株的全球基因组监测,对于加快大流行应对至关重要。