US measles cases now at 500+ in 20 states, first international spread

We're reaping the results of lax or no vaccination. For every thousand measles cases, someone dies—and we've already had two known deaths. And that's just the tip of the anti-public health iceberg.

This post is about rapidly spreading measles, but there’s much more going on in public health that will affect all of us in every part of our lives. Read Dr. Katelyn Jetelina’s summary of the danger.

Sections in this post

• Why it matters, particularly to women

• Cases are spreading rapidly

• So much for US leadership in eradication

• How bad is it (with graph) and how did we get here?

• Which are the 38 states where kids and pregnant women most vulnerable? (map)

• What can I do if I’m worried about unvaccinated family or friends? (with vaccine finder)

• Why is this “only the tip of the anti-public health iceberg?”

Why it matters

Women are the 24/7/365 chief medical officers for our immediate and extended families, and often the go-to person on health information at work and in the community. If you have a child or grandchild who lives in one of 38 (!) under-vaccinated states, those kids are are going to be far more exposed than in other states to measles and its complications—and 9 out of 10 unprotected kids or adults will catch it. At best, measles is a very uncomfortable illness, often accompanied by the pain of an ear infection every kid and parent dreads. At worst, it can be lethal.

Moderate and severe complications of measles include pneumonia or respiratory distress requiring hospitalization (1 out of 5 measles cases), encephalitis (leading to convulsions, deafness or brain damage), or even blindness or death from respiratory and neurologic complications. Complications are most common in children under 5 years and adults over age 30, and we’ve already seen one child and one adult death—the first in the US in over a decade.

The damage to the immune system is much more widespread, and the doctor who studies it says no one escapes damage. Measles causes ‘immune amnesia,’ leading the body to ‘forget’ how to protect itself against infection forever, leaving children and adults vulnerable to pathogens for years or for life. Measles infections destroy anywhere from 11% to 73% of a person’s antibody stockpile, deleting preexisting antibodies against other diseases. If anything argues against letting kids get it—let alone deliberately exposing kids to measles—in my mind, that’s it, particularly compared to the side effects of the vaccine. [Click for safety and side effects of MMR—the vaccine for measles, mumps and rubella.]

Finally, if a woman is pregnant and catches measles, she may deliver prematurely or have a low-birth-weight baby; both can be emotionally, physically, and economically debilitating.

Cases are spreading rapidly

There’s a military term that definitely applies here.¹ Fueled by anti-vaxers in Texas and liver-damaging information on inefective treatment spread by our own HHS Secretary, measles took off like a rocket this year with no end in sight, and now with more than 500 cases in 20 states. Each of those current cases is infecting more people at a rapid rate. Measles is one of the most contagious diseases on earth, spread by coughing and sneezing like COVID is. Also like COVID, those respiratory droplets can remain in a room—or an airplane cabin—for hours, waiting for an unsuspecting nose to inhale them.

Texas alone has had over 400 cases in three months, and that outbreak is genetically linked now to cases in three more states and Mexico—a rapidly-spreading fire.²

With the cat out of the Texas bag to this extent already, further spread of the disease in the US and internationally is inevitable. The two-week incubation period means most of those spreading the disease in the incubation period will not yet know they are ill. To put it clearly, one contagious person on a plane has the capability of spreading measles to multiple states and countries.

Looking at the US in total, there are already 523 known cases of measles right now, but statistics implicate likely thousands more unreported cases. Statistically, one to three measles deaths occur every 1000 cases or so, and we’d already had two deaths by early March when there were only 200 reported cases in Texas and New Mexico, both from the same outbreak. Those deaths infer we’ve almost certainly had at least 2000 cases so far this year—meaning thousands more people who were—and are— spreading the disease.

So much for US leadership eradicating measles

Measles was declared eliminated from the US—a historic achievement—in 2000, after no continuous disease spread the prior year. In 2019, with 1,274 cases, the US almost lost its world leadership status in eliminating measles.

2025 cases will almost certainly eclipse the 2019 total, taking our eradication status with it. The magnitude of the current US outbreak prompted a world-wide alert this week from the WHO. Losing eradication status will put us back on the same undesirable back stage as countries like Yemen, Afghanistan, and Kyrgyzstan, not known for public health leadership.

How bad is it? And how did we get here?

The two measles deaths this year were the first US measles deaths in over a decade. The graph below compares the 500+ cases in 20 states³ in the first three months of this year with total annual US cases since 2000. Measles spreads exponentially (not linearly), so the 500+ 2025 cases by late March will almost certainly eclipse the 2019 case rate. (Click on the graph and then the three ‘more’ buttons in upper right to enlarge the graph.)

Since the invention of the smallpox vaccine in 1796, there has always been anti-vax sentiment. US anti-vaxers were historically apolitical, but in the 2010s, that changed, first within ultra-conservative circles like the Tea Party, resulting in new blips in cases. Mid-2010s plans in California to eliminate the personal-belief exemption for school vaccinations raised more anti-vax sentiment, and political resistance spread more broadly within the party.

Wide use of social media facilitated the bombardment of vaccine disinformation. mobilizing anti-vax activists, and anti-COVID vaccine sentiment cemented politicized disinformation and boosted monetization of anti-vax information. By 2022, fewer than 60 Internet "actors” were the source of almost all vaccine disinformation

Political resistance peaked with COVID, and throughout the three years of the pandemic, MAGA supporters were least likely to get the COVID vaccine. Once resistance to any vaccination solidified, all vaccinations were painted with the same brush.

Where are kids and pregnant women most vulnerable to catching measles?

When more than 95% of people in a community are vaccinated, most people are protected through community, or “herd,” immunity—how the US got to eradicated status in 2000. In 2019, we were still at 95%, but with anti-vax sentiment during COVID, that plummeted nationally to 92.7% in 2023-2024. In the Texas county where the outbreak started, it was 82%, and a Texas pastor recently bragged about his school having the lowest vaccination rate (14.3%) in Texas.

Here’s what our vaccination rates look like today. To put it bluntly, if you live in an orange state—with vax rates <95%—and your child or grandchild is under- or unvaccinated, their odds of catching measles in an outbreak are 90%, and they are susceptible to mild and severe complications of measles, which can include brain damage or even death. [Find a vaccination site here.]

What can I do if I’m worried about family or friends who aren’t vaccinated?

Vaccine hesitancy is driven by a lack of confidence in public health science—cemented during COVID; a sense of low risk, buttressed by similar beliefs of others; and a lack of knowledge about why, when, and where to obtain vaccination.

While we have a long way to go to repair confidence in public health—including more coming confusion from HHS—the recent measles deaths woke many up. Very few of us can hear about a 6-year-old otherwise-health child dying of a completely preventable disease without being alarmed. Measles was no longer “something mild every kid gets.”

There are indications of emerging “vaccination enthusiasm.” Even though full immunization isn’t achieved until two measles vaccinations 3+ years apart, the first shot gives more protection than none. And parents who may have gotten their children the first shot, but not the second, will get full immunity for their child if they get the second vaccination now.

What you can do:

1. Bolster good science as much as you can. Pass this free post on if you think it might help.

2. Make sure they fully understand the risks, from mild (ear aches that keep kids and parents awake all night); to moderate (expensive and frightening hospitalization) and loss of immunity to common diseases; and severe, from encephalitis and blindness to even death. Talk about the healthy 6-year-old who needlessly died, as well as the adult who apparently died at home, perhaps alone, since help wasn’t sought. I can’t imagine the difficulty breathing and brain swelling he went through before dying.

3. Help them find vaccines, which are FREE. The most likely places are doctors’ offices, pharmacies, community health clinics, health departments and other community locations. Check Walgreens and CVS here, and watch for pop-up vaccine clinics locally. And here’s a national vaccination search site.

Wait…why is this only the tip of the anti-public health iceberg?

Because we—and the world—have always looked to our US Health and Human Services to lead in science and public health. And it’s being decimated.

Funding at the world-leading institution is being halted.⁴ Just this week, another $11 billion was cut from the HHS budget, and the agency fired another 10,000 workers, bringing the total employee loss to a quarter of HHS staff—and those are just the ones employed directly by HHS. At a time when universities and other research centers are finally making progress against once-deadly diseases (and diseases specific to women), funding is being slashed—even in the middle of promising studies—affecting up to 300,000 scientists nationally.

And that gets us back to Dr. Katelyn Jetelina, an internationally-recognized edpidemiologist, who spells the damage out far better than I ever could. Click here for her new post, Threats to public health at every angle.

Please stay finely tuned. Eventually this will turn around, but likely not until the chaos affects millions more than it already is. That’s when we’re all going to be needed to right the ship. And while I admit I’m an eternal optimist, history also says we will get there. Winston Churchill once said, “You can trust the Americans to do the right thing…after they try everything else.” IMO, we’re in the “trying everything else” phase now. I’ll be very, very happy when we finally move on.

1. Pick the most appropriate military term here.

2. The Texas outbreak has now been genetically linked to cases in New Mexico, Oklahoma, Kansas and Mexico. There are likely other US (and possibly elsewhere internationally) cases that originated with the Texas outbreak as well but have not yet been genetically linked to that outbreak.

3. Alaska, California, Florida, Georgia, Kansas, Kentucky, Maryland, Michigan, Minnesota, New Jersey, New Mexico, New York City, New York State, Ohio, Pennsylvania, Rhode Island, Tennessee, Texas, Vermont, and Washington.

4. I’ve covered the “why” elsewhere, and will be updating that with more information soon. The basics: the president needs $4.6 trillion in expenditures to extend his tax cut, of which those making $450,000 or more this year (the top 5% of households) will get about half, leaving the other 323 million of us (95%) to claw at each other for the other half.