Measles: What's Going on With Measles?

In 2025, we heard a lot about measles — there was an outbreak in Texas, a child died, and the news was full of stories focused on what was happening. In my Wednesday Q&A on Instagram, I was consistently getting many questions about what was going on, whether to be worried, and so on.

In 2026, that has faded. Google searches for “measles” are at only about 10% of what they were in early 2025. In my own audience, people aren’t asking about this anymore, at least not at close to the same level.

This change doesn’t reflect a change in the measles situation — more on this below, but, in short, the measles situation has gotten worse. Instead, I think the change in interest reflects the fact that this isn’t new. News coverage tends to focus on items that are “newsworthy” — and one important component of this is surprise. Unfortunately, the fact that there are a lot of measles cases in the U.S. is no longer surprising.

This loss of attention feels deeply problematic to me, for two reasons. First, it decreases the chance that individuals will take actions to protect themselves. And, second, it reduces the urgency around addressing what has happened to get us here.

Today: an update on where measles is in the U.S. right now, why we got here, how concerned individual parents should be, and what you can do to protect yourselves and others.

A note: if you’re interested in more about what measles looks like, the symptoms, and treatments, check out our Measles 101 article.

Take me to the bottom line

What is going on with measles?

In the U.S., measles is a notifiable disease, meaning the CDC keeps detailed weekly records of cases. The graph below shows measles cases, by week, since 2022.

For the 2022–2024 period, there were virtually no measles cases. This follows a long trend. In 2014 and 2019, the U.S. saw medium-sized outbreaks, but otherwise, most weeks had no cases recorded.

This changed in 2025 with the outbreak in Texas. As that outbreak ended, measles cases continued at a low level. In early 2026, however, a significant new outbreak has shown up. Measles cases in week 3 of 2026 were at 279. This is the highest number of cases for a single week in decades.

But more significantly, this single week in 2026 saw more cases than the yearly total in all but five years since 2000. Cases have come down in the following weeks, although reporting is incomplete for the most recent week.

Currently, measles cases are clustered around a small number of outbreaks. The graph below shows total cases by state so far in 2026 for all states with positive cases. The largest current outbreak is in South Carolina, followed by Utah and Arizona. Most states in the U.S. do not currently have any measles cases, reflecting the outbreak nature of the disease. Either you’ve got an outbreak and it’s spreading fast, or you do not (yet).

Most of the cases are in children under 19, and children under 5 have the highest hospitalization rate. In 2025, the overall hospitalization rate for measles cases was 11%, but 18% for children under 5. There were 3 measles deaths in 2025. Unfortunately, we should expect more than that number in 2026.

Why are there so many cases?

The short answer: vaccination rates for measles have gone down, and that has driven the upswing in cases. The CDC has documented a slow decline in vaccination rates for children entering kindergarten — from 95% in 2010–2011 to an estimated 92.5% in the 2024–2025 school year.

This decline may not seem large, but it has had a large impact for two reasons. First, the decline is not uniform — some states and local areas have much lower vaccination rates. Since disease spread is local, this matters. South Carolina and Utah have estimated MMR vaccination rates of 91% and 88%, respectively, versus (for example) almost 98% in Maine.

A decline of this size is also important because measles is extremely contagious — in an unprotected population, a single person with measles is expected to infect 12 to 18 other people. The virus can live for long periods on surfaces, making it even more difficult to prevent spread. For this reason, we need a very high vaccination rate in an area — typically over 97% — to generate herd immunity.

Declining vaccination rates increase the chance that a measles outbreak takes hold if the virus is introduced, especially in an area with low vaccination rates. This is what we are seeing now.

Is my child at risk?

Two doses of the MMR vaccine are extremely protective against measles; almost 95% of the recent cases are in unvaccinated children or adults. If your child has received two doses of MMR, you should be confident in their protection. Measles immunity is also sterilizing, meaning that vaccination does more than just prevent you from getting sick. It also prevents you from spreading the virus.

For children between the ages of 1 and 4 who have had only one dose of the MMR vaccine, protection is also very, very high — 95% of children develop immunity after a single MMR dose (this goes to 99% after two doses). If you’ve got a child who had one dose of the vaccine between 12 and 15 months, they are also very well protected. (You can also get them the second dose early — as soon as a few months after the first.)

Babies younger than a year typically have some protection if their mom was vaccinated or had measles in the past — this is, in fact, why the first dose of the vaccine is given at 12 months. When it’s given before that, some babies do not respond because of maternal exposure. However, the first MMR dose can be given early — as early as 6 months — especially if there is a concern about possible exposure. Babies who are vaccinated at this point will need two additional doses — one at 12 to 15 months, and one at 4 years.

A lot of parents are understandably concerned, especially with babies under 6 months who have not had any vaccines. Despite some protection from maternal antibodies, this group remains at risk, and that risk is elevated when there are more measles cases. Having said that, it’s important to keep this risk in some perspective. The CDC estimates there have been 20 million cases of the flu this season, and during that same period, there have been under 1,000 cases of measles. The risks here are still, therefore, relatively small even if they aren’t as small as they should be.

Where will we go from here?

I wish I had something more positive to say, but things are likely to get worse before they get better. There are many states and local areas where vaccination rates are low enough that an outbreak could get started and would be difficult to stop. Given the increasing number of cases, the chance that someone who is infected travels to a vulnerable location is increasing.

We are also likely to see more hospitalizations and deaths. In 2025, the death rate from measles was 0.13%, or slightly more than 1 in 1,000 cases. If the current case rate continues to track upward, deaths will track up too.

How bad the situation will get depends, in part, on what happens with vaccination rates. The current administration is, in my view, doing their best to erode trust in vaccines and make them more difficult to access. This is likely to cause vaccination rates to further decrease. On the flip side, as cases rise, more people may want to vaccinate to protect their children. Ultimately, we’ll need more data to see what dominates.

What can I do?

Two simple things.

First, if your child is over 1 year and hasn’t had the MMR vaccine, please get them vaccinated.

Second, if you have friends or family who are unsure about the safety of vaccines, please consider sharing this article about vaccine safety — it’s free and does not require a ParentData membership to read.

The good news is that we do have a safe and effective way to prevent measles; now we just need to do it.

The bottom line

As vaccination rates have declined, measles cases have been rising in the U.S. since 2025, with no sign of slowing down.
Just one dose of the MMR vaccine is extremely protective against measles (two doses even more so); the vast majority of measles cases are in unvaccinated children or adults.
Babies younger than a year are the most vulnerable, but they typically have some protection if their mom was vaccinated or had measles in the past.
Unfortunately, this is likely to get worse before it gets better. It is crucial to get vaccinated, get your children vaccinated, and talk to your friends and family who are vaccine-hesitant.