Understanding the causes and consequences of the emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants of concern is crucial to pandemic control yet difficult to achieve because they arise in the context of variable human behavior and immunity. We investigated the spatial invasion dynamics of lineage B.1.1.7 by jointly analyzing UK human mobility, virus genomes, and community-based polymerase chain reaction data. We identified a multistage spatial invasion process in which early B.1.1.7 growth rates were associated with mobility and asymmetric lineage export from a dominant source location, enhancing the effects of B.1.1.7’s increased intrinsic transmissibility. We further explored how B.1.1.7 spread was shaped by nonpharmaceutical interventions and spatial variation in previous attack rates. Our findings show that careful accounting of the behavioral and epidemiological context within which variants of concern emerge is necessary to interpret correctly their observed relative growth rates.

了解令人关注的严重急性呼吸综合征冠状病毒 2 (SARS-CoV-2) 变体出现的原因和后果对于控制大流行至关重要，但实现起来却很困难，因为它们是在人类行为和免疫力变化的背景下出现的。我们通过联合分析英国人类流动性、病毒基因组和基于社区的聚合酶链式反应数据，研究了谱系 B.1.1.7 的空间入侵动态。我们确定了一个多阶段的空间入侵过程，其中早期 B.1.1.7 增长率与从主要来源位置的流动性和不对称谱系输出相关，从而增强了 B.1.1.7 增加的内在传播性的影响。我们进一步探讨了非药物干预措施和先前发病率的空间变化如何影响 B.1.1.7 的传播。我们的研究结果表明，有必要仔细考虑所关注变量出现的行为和流行病学背景，以正确解释观察到的相对增长率。