The death toll of hospitalized patients in the United States has rebounded to the highest level since February this year, and there is a shortage of intensive care beds in some parts of the south. Three more senators had "breakthrough infection". The number of new deaths in the United States peaked in January this year, then gradually decreased, and fell to the bottom in July. However, with the spread of the delta strain of the new crown variant virus, the epidemic has rebounded in the past month, and the number of single day deaths has continued to increase.