Severe COVID-19 is rare in previously healthy individuals who are less than 50 years of age, affecting probably no more than 1 in 1,000 such infected individuals. We suggest that these patients may become critically ill because of monogenic inborn errors that disrupt protective immunity to SARS-CoV-2. Why do some young and previously healthy individuals develop severe COVID-19? In this Comment, Casanova and colleagues suggest that monogenic inborn errors of immunity may be responsible based on lessons from other viral infections.

中文翻译：

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年轻人和健康人中的严重 COVID-19：单基因先天性免疫缺陷？

严重的 COVID-19 在以前健康的 50 岁以下的个体中很少见，影响可能不超过 1,000 名此类感染者中的 1 人。我们认为，这些患者可能会因为破坏对 SARS-CoV-2 的保护性免疫的单基因先天性错误而患重病。为什么一些年轻且以前健康的人会患上严重的 COVID-19？在这篇评论中，Casanova 及其同事认为，基于其他病毒感染的教训，单基因先天性免疫错误可能是造成这种情况的原因。