The share of U.S. counties where 95 percent or more of kindergartners were vaccinated against measles — the number doctors say is needed to achieve overall protection for the class, known as “herd immunity” — has dropped from 50 percent before the pandemic to 28 percent, according to The Post’s examination of the public records from 44 states and the District of Columbia.
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- archive.today — has text, but interactive map with school-specific vaccination rate information and graphics do not work


This is what collapse looks like.