Measles

Measles FAQ

Am I protected against measles? – The CDC considers you protected from measles if you have written documentation (records) showing at least one of the following:

  • You received two doses of measles-containing vaccine; and you are
    • A school-aged child (grades K-12)
    • An adult who will be in a setting that poses a high risk for measles transmission (including students at post-high school education institutions, healthcare personnel, and international travelers)
  • You received one dose of measles-containing vaccine, and you are:
    • A preschool-aged child
    • An adult who will not be in a high-risk setting for measles transmission
  • A laboratory confirmed that you had measles at some point in your life.
  • A laboratory confirmed that you are immune to measles.
  • You were born before 1957.

Do I ever need a booster vaccine? – No. The CDC considers people who received two doses of measles vaccine as children according to the U.S. vaccination schedule protected for life and they do not ever need a booster dose.

I am an adult now but only got one dose of measles vaccine as a child.  Do I need a second dose? – If you were born after 1957, one dose of measles vaccine is sufficient to be considered protected from measles. Certain adults may need 2 doses. Adults who are going to be in a setting that poses a high risk for measles transmission should make sure they have had two doses separated by at least 28 days. These adults include:

  • Students at post-high school education institutions
  • Healthcare personnel
  • International travelers
  • People who public health authorities determine are at increased risk for getting measles during a measles outbreak

How effective is the measles vaccine? – The measles vaccine is very effective. Two doses of measles vaccine are about 97% effective at preventing measles of exposed to the virus. One dose is about 93% effective.

How long does it take for the measles vaccine to work in your body? – People are usually fully protected after about 2-3 weeks.