Q6. When do you estimate the United States will achieve herd immunity? What about globally? #AskReuters

Caroline Humer

@CarolineHumer Hi Caroline. That is the million dollar question. The short answer is that nobody is quite sure #AskReuters /1

@CarolineHumer That said, we may get to herd immunity after vaccinating a smaller % of the population. First, previously infected people contribute to herd immunity which is relevant in many states (NY, NJ, Dakotas &amp; others...) #AskReuters /3

Fred Hutch / UW, Infectious diseases, Physician, Scientist and Math modeler