响应号召，请大家指正

周一，美国达到了一个严峻的里程碑，确认了超过1000万例病例，并且几乎每个州的病例数都在继续增加。

On Monday, the coronavirus disaster in the US reached a new severe level: more than 10 million confirmed cases have been reported and the numbers are still counting in almost every state. 

我觉得里程碑更多的情况应该是指代好的事情。