Measles Vaccine Guidelines and Recommendations

We’ve received numerous inquiries from adult patients regarding their immunity to measles. A recent outbreak in West Texas has caused a notable increase in reported cases, with 378 confirmed cases as of March 20, 2025, compared to just 285 cases throughout 2024. This rise highlights the importance of understanding measles immunity and vaccination guidelines.

Measles is a highly contagious viral infection that spreads through respiratory droplets.

Immunity Status by Birth Year

•   Individuals born before 1957 are generally considered immune to measles due to likely exposure to the virus during childhood.

•   Individuals born after 1957 who received a measles vaccine prior to 1968 may have received an inactivated (killed) vaccine. Between 1963 and 1967, a killed vaccine was used, which was not as effective as the live vaccine introduced later. If you were vaccinated in the 1960s, you may not need revaccination if you have documentation of receiving the live vaccine.

What Should You Do If You Received the Killed Vaccine?

If you received the inactivated measles vaccine, you should consider getting revaccinated with at least one dose of the live attenuated measles vaccine. If you're unsure which vaccine you received, you have two options:

1.     Check a Measles Titer: A titer test measures the level of antibodies in your blood, which can indicate immunity or past exposure to measles.

2.     Get an MMR Booster: You can schedule a booster at your pharmacy or local health department. Even if you are already immune, receiving a booster is not harmful.

Who Should Not Receive the MMR Vaccine?

While the MMR vaccine is generally safe, there are specific groups who should avoid it, including:

•   Pregnant women

•   Severely immunocompromised individuals

•   Anyone with an allergy to the MMR vaccine

•   Those who have recently received blood products or another live vaccine within the past 4 weeks

If you have any concerns about whether the MMR vaccine is safe for you, please consult with your healthcare provider.

Why Are People Concerned About Measles?

Many patients who inquire about their immunity status are often concerned because they:

•   Travel internationally

•   Have close contacts who are not vaccinated

•   Spend time with infants under one year of age who have not yet received the vaccine

Protection and Preventive Measures

Measles is an extremely contagious virus, and nearly everyone who hasn’t been vaccinated will become infected if exposed. However, if you receive the MMR vaccine within 72 hours of exposure, you may gain some protection or experience a milder illness.

It's important to note that while the MMR vaccine effectively prevents measles, it has not been shown to prevent mumps or rubella in individuals who are already infected with those viruses.

 Read more about the recommendations from one of our Ms. Medicine colleagues here:

https://www.eileenwestmd.com/blog/measles-guidelines-and-recommendations/