The majority of people infected with SARS-CoV-2 are asymptomatic or have mild to moderate symptoms. However, for unknown reasons, about 15 % have severe pneumonia requiring hospital care and oxygen support, and about 5 % develop acute respiratory distress syndrome, septic shock, and multiorgan failure that result in a high mortality rate. The risk of severe COVID-19 is highest among those who are over 70 years of age. Why severe COVID-19 develops in some people but not others is not understood. Could some cases involve reactivation of latent cytomegalovirus (CMV)?

中文翻译：

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巨细胞病毒的重新激活是否会导致严重的COVID-19疾病？

感染SARS-CoV-2的大多数人无症状或有轻度至中度症状。但是，由于未知原因，约15％的人患有严重的肺炎，需要医院护理和氧气支持，约5％的人患有急性呼吸窘迫综合征，败血性休克和多器官衰竭，导致高死亡率。在70岁以上的人群中，发生严重COVID-19的风险最高。为什么有些人会出现严重的COVID-19，而另一些人却没有。某些情况下可能涉及潜在巨细胞病毒（CMV）的重新激活吗？