德国抽查了海因斯伯格400个家庭1千人的血液，发现15%的人已有针对新冠病毒的抗体，是德国确诊病例的6倍，由此算出新冠病毒感染死亡率是0.37%。丹麦4月初抽查了1千名献血者，3.5%有针对新冠病毒的抗体，是确诊病例的14倍。这两项研究表明绝大部分感染者都无症状或只有轻微症状，死亡率比已知的低得多。

Let me be clear. This virus has a lethality substantially in excess of “seasonal” flu. Yes, up to half of those infected might not show symptoms. But that is accounted for in our estimates and always was. There is no credible data supporting the idea that 90% are asymptomatic.