“Coverage in a given community, when it falls below a certain critical level, you get the kinds of outbreaks that we’re seeing, particularly in places like New York City and the Williamsburg section of Brooklyn…. his is a relatively closed community, a Hasidic Jewish community in that area — that are not vaccinating their children at a rate that would provide that broad umbrella of protection that we call herd immunity…When you drop down to the 80s or even the 70s [emphasis added] or even lower, where it is now in that community, that’s exactly the explanation of why we’re seeing the outbreaks that we’re seeing.”