How Does the Measles Vaccine Work?
The measles vaccine works by using a component of the measles virus to stimulate your immune system. This process helps your body produce antibodies that will recognize and fight the measles virus if you’re exposed to it in the future.
While the vaccine doesn’t cause the disease, it prepares your immune system to respond quickly, and effectively, if you're ever exposed.
With two vaccine doses the vaccine provides strong, lasting protection and reduces the risk of serious complications such as pneumonia or brain swelling.
Did I Receive the Measles Vaccine?
The MMR vaccine is usually given in two doses: the first at 12 to 15 months of age and the second between 4 and 6 years of age.
In all 50 states, the MMR vaccine is a required vaccination for children entering childcare, kindergarten, and school, ensuring that students are protected as they begin their education.
However, some states allow exemptions for medical, religious, or philosophical reasons, so requirements may vary. Vaccination rates also differ from community to community.
Can You Still Get Measles if You’ve Been Vaccinated?
The MMR vaccine is about 97% effective when both doses are received.
While no vaccination provides 100% protection, the measles vaccine is highly effective. Although rare, there is a slight chance of contracting measles after coming in contact with the disease after being vaccinated.
However, people who do contract the virus typically experience a much milder form, with fewer complications, than those who are unvaccinated.
How Long Does the Measles Vaccine Last?
For most people, the MMR vaccine, which is given in two doses, provides lifelong protection against measles, mumps, and rubella.
Once vaccinated, you gain strong protection, with only a small percentage of people requiring a booster later in life. This includes those at higher risk, such as healthcare workers, individuals traveling to areas with measles outbreaks (both internationally and within the U.S.), and those who were vaccinated before 1971, prior to the availability of the current vaccine.
If you are on certain medications, or have a condition that weakens your immune system, this may affect vaccine effectiveness. Talk to your doctor about any concerns you may have.
The MMR Vaccine and Adults
Adults who have not received the MMR vaccine may still need it, particularly if they are at risk of exposure to measles, mumps, or rubella.
If you were born after 1957 and did not receive the vaccine as a child, or if you only received one dose, it's recommended to get vaccinated.
For adults who have not been vaccinated, the MMR vaccine is typically given in two doses, with the second dose given at least 28 days after the first.