Measles is making a troubling comeback in the U.S., driven by declining vaccination rates and rising vaccine hesitancy.

These new steps dovetail with a rapid rise in measles cases this year, with more than 600 cases reported across at least 21 states.

U.S. measles cases in six states now exceed 700, and two children and an adult have died. A look at the situation in each ...

As families hit the roads, trains, and skies for spring break, health officials warn about the spread of measles.