How holes in herd immunity led to a 25-year high in U.S. measles cases

Too many unvaccinated people are helping the virus spread

Los Angeles County health officials

IT’S AN ORDER  Public health officials in Los Angeles County on April 26 discuss the quarantine orders in place for hundreds of students at two Los Angeles universities after they potentially were exposed to measles.

Damian Dovarganes/ASSOCIATED PRESS

Measles is so contagious that the virus can unerringly find the unvaccinated.