December 30, 2025
As a pediatrician, I know there are so many things parents have to worry about. It is unfortunate a worry has been added back to the list that parents haven’t had to think about for years: measles. While most Utahns are protected by vaccination, unvaccinated babies are at risk. I think it is important for Utah parents to know there is an option to give their baby a measles vaccine (MMR) as early as when they turn 6 months old. If you’re trying to figure out if you want to give your baby the early shot I encourage you to talk to your baby’s doctor or provider. Here is some info for you to consider.
First—why should you even consider getting the early measles vaccine for your baby?
Unfortunately, many people have gotten sick with measles in Utah in the past months. This virus is now spreading in many Utah communities. Concerningly, we have had babies get exposed while waiting at clinics when people who have measles come in for care. While surrounding your baby with vaccinated people is a key way to shield them, they do not protect them for these unpredictable exposures.
What are the downsides to giving your baby an early measles vaccine?
One extra shot: Babies’ immune systems aren’t mature enough to fully respond to the vaccine, so they will also need to get the normal two shots later. Usually there is no risk of measles in Utah so we don’t want to give them an extra shot. But now the risk of measles is real enough it is reasonable to consider giving an extra shot, even if it does mean a sore arm and a grumpy baby for a day.
Change to long term immunity: There is a small set of data that suggests kids who were vaccinated early may have a slight decrease in measles protection, however, on review the risk appears to be minimal. There is a real and current risk of measles in Utah, so the balance weighs toward giving protection now even if there is a theoretical risk of a slight decrease in protection later.*
Is it safe to give the vaccine early?
The MMR vaccine has been used for decades and most of us got it as kids. It has been extremely well studied and is a very safe vaccine. Giving the vaccine to babies earlier does not change those risks. Quite a few kids will get a low fever and, if they were old enough to tell us, probably many have a sore arm and achy joints. But those side effects are minor compared to the symptoms of measles.
My take away
The risk of measles is real in our community right now. It still is very small—somewhere around 60 babies have been exposed to measles while in clinics—but the risk exists. I think it is reasonable to consider getting an early shot for your baby. Talk to your doctor if you are thinking about the early shot and together you can determine if it is right for your family.
Dr. Leisha Nolen, Utah state epidemiologist
* When we reviewed scientific studies, we found a small number that looked at how an early MMR vaccine affected a baby’s long-term immunity. Most of these studies are quite old (from the 1980s and 90s). The studies focused on how many antibodies the child had after they were fully vaccinated. Antibodies are a key part of our immune system that fight off infections. BUT we also have a second part of the immune system: immune cells. Both antibodies and immune cells keep us healthy. Antibodies are like targeted assassins while immune cells are general warriors looking for the bad guys. The data show that kids who got a dose before they turned 1 had fewer antibodies than those who got their first dose after they turned 1. However, kids who are vaccinated early have been found to have immune cells that could stop measles just as well as kids vaccinated at the normal time. Of course, high immune cell activity or low antibody numbers aren’t what we care about. What really matters is if the kid’s immune system can fight off measles. Over the past few decades it has been very hard to study how well someone can fight off measles since there have been so few measles infections. But the few studies where kids were exposed to measles suggest that kids who were vaccinated early were just as good at fighting off measles as those kids who just got the normal 2 later doses.