It’s simple: Get vaccinated.

You get two doses of the MMR vaccine. Children usually get the first dose when they are 12 months old, and a second before kindergarten.

On its web site, the CDC calls the vaccine “very effective” and states that “one dose is about 93% effective at preventing measles and two doses about 97% effective.”

Before the vaccination program started, 3-4 million people per year in the U.S. got measles, and 400-500 of them died, the CDC estimates.

Do adults need the MMR vaccine?

If you got two doses as a child, you’re covered for life. You don’t need a booster shot.

If you weren’t vaccinated, you may need it. “Generally, anyone 18 years of age or older who was born after 1956 should get at least one dose of MMR vaccine, unless they can show that they have either been vaccinated or had all three diseases [measles, mumps, and rubella],” the CDC’s web site states.

Pregnant women shouldn’t get vaccinated until after they’ve had their baby. People who are allergic to the vaccine’s ingredients shouldn’t get it, either.

Not sure? Ask your doctor.

If you think you’ve been exposed to measles and haven’t been vaccinated, can you still get the vaccine?

Yes, but you have to get it within 72 hours of exposure to be effective.

For more information, please see WEB MD