Bloomberg说美国新冠都第三波了.而且每一波新冠达到峰值的时间都越来越久.
https://www.bloomberg.com/news/articles/2020-11-11/this-covid-surge-is-america-s-longest-and-it-s-getting-longer
https://www.bloomberg.com/news/articles/2020-11-11/this-covid-surge-is-america-s-longest-and-it-s-getting-longer