SARS-CoV-2 lineage B.1.1.7, a variant that was first detected in the UK in September 2020¹, has spread to multiple countries worldwide. Several studies have established that B.1.1.7 is more transmissible than pre-existing variants, but have not identified whether it leads to any change in disease severity². Here we analyse a dataset that links 2,245,263 positive SARS-CoV-2 community tests and 17,452 deaths associated with COVID-19 in England from 1 November 2020 to 14 February 2021. For 1,146,534 (51%) of these tests, the presence or absence of B.1.1.7 can be identified because mutations in this lineage prevent PCR amplification of the spike (S) gene target (known as S gene target failure (SGTF)¹). On the basis of 4,945 deaths with known SGTF status, we estimate that the hazard of death associated with SGTF is 55% (95% confidence interval, 39–72%) higher than in cases without SGTF after adjustment for age, sex, ethnicity, deprivation, residence in a care home, the local authority of residence and test date. This corresponds to the absolute risk of death for a 55–69-year-old man increasing from 0.6% to 0.9% (95% confidence interval, 0.8–1.0%) within 28 days of a positive test in the community. Correcting for misclassification of SGTF and missingness in SGTF status, we estimate that the hazard of death associated with B.1.1.7 is 61% (42–82%) higher than with pre-existing variants. Our analysis suggests that B.1.1.7 is not only more transmissible than pre-existing SARS-CoV-2 variants, but may also cause more severe illness.

SARS-CoV-2 谱系 B.1.1.7 是 2020 年 9 月在英国首次发现的一种变体¹，现已传播到全球多个国家。几项研究已经确定 B.1.1.7 比先前存在的变体更容易传播，但尚未确定它是否会导致疾病严重程度的任何变化²。在这里，我们分析了一个数据集，该数据集将 2020 年 11 月 1 日至 2021 年 2 月 14 日期间英国 2,245,263 次 SARS-CoV-2 阳性社区测试和 17,452 例与 COVID-19 相关的死亡联系起来。对于这些测试中的 1,146,534 次（51%），存在或不存在B.1.1.7 可以被识别，因为该谱系中的突变阻止了刺突 ( S ) 基因目标的 PCR 扩增（称为S基因目标失败 (SGTF) ¹). 基于已知 SGTF 状态的 4,945 例死亡，我们估计在调整年龄、性别、种族、剥夺、居住在疗养院、地方当局的居住地和测试日期。这相当于一名 55-69 岁男性在社区检测呈阳性后 28 天内死亡的绝对风险从 0.6% 增加到 0.9%（95% 置信区间，0.8-1.0%）。纠正 SGTF 的错误分类和 SGTF 状态的缺失，我们估计与 B.1.1.7 相关的死亡风险比先前存在的变体高 61% (42–82%)。我们的分析表明，B.1.1.7 不仅比先前存在的 SARS-CoV-2 变体更具传播性，而且还可能导致更严重的疾病。