Most parents understand that the first dose of the MMR vaccine is routinely given to children when they are 12 to 15 months old, at least in the United States.
In some other countries, the first dose is routinely given as early as 8 to 9-months of age.
And in high-risk situations, the MMR can safely be given to infants as early as age 6-months.
Is the MMR Safe for 6 Month Old Babies?
An early MMR, is that safe?

Yes, it is safe.
What about the package insert?
“Local health authorities may recommend measles vaccination of infants between 6 to 12 months of age in outbreak situations. This population may fail to respond to the components of the vaccine. Safety and effectiveness of mumps and rubella vaccine in infants less than 12 months of age have not been established. The younger the infant, the lower the likelihood of seroconversion (see CLINICAL PHARMACOLOGY). Such infants should receive a second dose of M-M-R II between 12 to 15 months of age followed by revaccination at elementary school entry.”
MMR II Package Insert
The package insert says to give infants who get an early dose another dose when they are 12 to 15 months old! It doesn’t say to not protect these babies!
But what about the idea that the safety and effectiveness of MMR hasn’t been proven for infants under 12 months of age?
In general, the package insert is only going to list studies that the manufacturer used to get FDA approval for their vaccine. Since it is an off-label recommendation of the ACIP, they would not include the studies that show that an early MMR is safe and effective.
“In conclusion, this study indicated that the MMR was well tolerated and immunogenic against measles, mumps and rubella with schedule of first dose both at 8 months and 12 months age. Our findings strongly supported that two doses of MMR can be introduced by replacing the first dose of MR in current EPI with MMR at 8 months age and the second dose at 18 months in China.”
He et al on Similar immunogenicity of measles-mumps-rubella (MMR) vaccine administrated at 8 months versus 12 months age in children.
Before 8 months, an early MMR isn’t likely to be as effective as giving it later. That’s because some maternal antibodies might linger in a baby’s system and can interfere with the vaccine working, even after six months. How many antibodies and how much interference?
It’s almost impossible to tell for any one child, but the risk that this maternal protection has begun to wear off and these infants are at risk to develop measles is too great. That’s the reason that they get an early MMR, even though we know it won’t be as effective as a dose given later and we know it will have to be repeated.
Is this early dose safe?
“This review did not identify any major safety concerns. These findings may facilitate discussions about the risks and benefits of vaccinating infants who are potentially exposed to this life-threatening disease.”
Woo et al on Adverse Events After MMR or MMRV Vaccine in Infants Under Nine Months Old
Of course! Although the complications of measles can be serious, even deadly, we aren’t going to recommend something that is even worse.
“Early MMR vaccination is well tolerated, with the lowest AE frequencies found in infants aged 6-8 months. It is a safe intervention for protecting young infants against measles.”
van der Maas et al on Tolerability of Early Measles-Mumps-Rubella Vaccination in Infants Aged 6-14 Months During a Measles Outbreak in The Netherlands in 2013-2014.
So an early MMR is safe, with few risks, and is likely effective at preventing measles.
And by now you know what’s not safe. That’s right, getting measles.
More on Early MMR Vaccines
- VAXOPEDIA – How to Avoid Getting Caught up in a Measles Outbreak
- VAXOPEDIA – Everything You Need to Know About the Measles Vaccine
- VAXOPEDIA – What to Do If Your Child Is Exposed to Measles
- VAXOPEDIA – Who Needs an MMR Vaccine?
- VAXOPEDIA – Why Are You Still Worried About the MMR Vaccine?
- VAXOPEDIA – The Myth That Measles Isn’t Deadly
- VAXOPEDIA – Who Is at Risk If You Don’t Vaccinate Your Kids?
- VAXOPEDIA – Who Dies with Measles?
- VAXOPEDIA – Why Are We Having Measles Outbreaks If MMR Vaccination Rates Are Not Declining?
- VAXOPEDIA – What Are the Signs and Symptoms of Measles?
- VAXOPEDIA – How Contagious Is Measles?
- VAXOPEDIA – How Often Should You Do Vaccine Titer Testing?
- VAXOPEDIA – News on the Latest Measles Outbreaks of 2019
- Study – Adverse Events After MMR or MMRV Vaccine in Infants Under Nine Months Old.
- Study – Similar immunogenicity of measles-mumps-rubella (MMR) vaccine administrated at 8 months versus 12 months age in children.
- Study – Tolerability of Early Measles-Mumps-Rubella Vaccination in Infants Aged 6-14 Months During a Measles Outbreak in The Netherlands in 2013-2014.
- Study – Effectiveness of Early Measles, Mumps, and Rubella Vaccination Among 6-14-Month-Old Infants During an Epidemic in the Netherlands: An Observational Cohort Study.
- Study – Protecting infants against measles in England and Wales: a review.
- Study – An outbreak of measles in an undervaccinated community.
- CDC – Measles Vaccination
- MMR ACIP Vaccine Recommendations (Measles, Mumps and Rubella)
- Ask the Experts about Measles, Mumps, and Rubella (MMR) Vaccines
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- Measles Victim Calls For Mass Vaccination Events in Frum Communities Worldwide
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