Is an MMR Booster for Adults Necessary?

With the current measles outbreak showing no sign of letting up, you may be wondering: If I’m fully vaccinated, am I at risk?
Still, Fuller says it’s vital to know your vaccination and health history, and whether you may benefit from an MMR vaccine booster if you’re in a vulnerable group.
U.S. Measles Outbreak: What’s the Latest?
Of those people infected, 116 have been children younger than 17 — the majority of those (79) were unvaccinated, while 62 have unknown vaccination status.
Who Should Consider an MMR Booster?
Public health authorities recommend consulting with your healthcare provider to check if you might be among those who could benefit from a booster or revaccination. Those who might consider a booster include:
- People Who Have Had Just One Measles Shot A single dose of the MMR vaccine is around 93 percent effective at preventing measles, whereas two doses are considered fully protective at about 97 percent effectiveness. Public health officials specifically underscore that healthcare workers, college students, some people with HIV, and family members and close contacts of people with compromised immune systems also receive a second dose if they have received only one dose.
- People Vaccinated Between 1968 and 1989 “There may be some gap in immunity, as during that time only one dose was recommended,” says Catherine Troisi, PhD, a professor of management policy and community health at the UTHealth Houston School of Public Health. Still, adults born during or after 1957 who received at least one dose of live measles virus-containing vaccine (MMR) on or after their first birthday should be protected against measles in most cases. (Note: People born before 1957 are likely to have been infected and are presumed to be protected against measles, mumps, and rubella.)
- People Vaccinated Between 1963 and 1967 Adults may have been vaccinated during these years with either inactivated (killed) measles vaccine or measles vaccine of unknown type. They should be revaccinated with at least one dose of live, attenuated measles vaccine (MMR). A killed measles vaccine available during this time and given to a small percentage of the population was not as effective.
- People Who Are Unsure of Their Vaccination Status Saahir Khan, MD, PhD, an infectious disease specialist with Keck Medicine of USC in Los Angeles, advises getting a two-dose series of MMR vaccine if you are unsure of your vaccine status. “There is no increased risk from additional doses,” says Dr. Khan.
Why Is the MMR Vaccine Important for Preventing Measles?
“As healthcare providers, community leaders, and policymakers, we have a shared responsibility to protect public health,” Kennedy wrote in a FoxNews.com op-ed that was also posted to the HHS site. “This includes ensuring that accurate information about vaccine safety and efficacy is disseminated. We must engage with communities to understand their concerns, provide culturally competent education, and make vaccines readily accessible for all those who want them.”
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Emily Kay Votruba
Fact-Checker

Don Rauf
Author
Don Rauf has been a freelance health writer for over 12 years and his writing has been featured in HealthDay, CBS News, WebMD, U.S. News & World Report, Mental Floss, United Press International (UPI), Health, and MedicineNet. He was previously a reporter for DailyRx.com where he covered stories related to cardiology, diabetes, lung cancer, prostate cancer, erectile dysfunction, menopause, and allergies. He has interviewed doctors and pharmaceutical representatives in the U.S. and abroad.
He is a prolific writer and has written more than 50 books, including Lost America: Vanished Civilizations, Abandoned Towns, and Roadside Attractions. Rauf lives in Seattle, Washington.