Are all measles vaccinations good for life?

While measles vaccines usually provide lifelong protection, federal health authorities say that some people born before 1968 may have received a less effective vaccine and should get a booster. 

Between 1963 and 1967, some measles, mumps and rubella vaccines contained an inactivated measles virus, which was less effective than the standard live vaccine. The Centers for Disease Control and Prevention recommends that recipients of the inactivated vaccine, and those unsure of which vaccine they received, get a second MMR shot.

Two doses of the standard MMR vaccine are 97% effective against measles for life.

Though the Pan American Health Organization declared the U.S. measles-free in 2000, more than 1,280 measles cases have been reported across the country so far this year. As of March 12, Colorado had reported 10 confirmed cases, most tied to an outbreak in Broomfield, and all involving people who were unvaccinated.