"If a herd immunity strategy is pursued, meaning no further government intervention is taken from now to Jan 1st, the death toll could increase to 620,000," according to IHME's briefing. The death rate could reach an unprecedented 3,000 a day by December, due in part to "declining vigilance of the public," the IHME expects. For now, the model points to declining mask use in some regions from peak usage in early August.