The first measles death in the US in a decade is NOT normal.

Here's what you should know about how to keep you and your loved ones safe.

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I was all ready to publish a completely different article today about the flawed pre-print on COVID-19 vaccines and the flawed interpretations from many prominent “scicomm” accounts (that one is coming tomorrow, promise), but with the ongoing measles outbreak in Texas and the first death due to measles in the US in a decade, I want to cover this more urgent topic.

This is not remotely the first time I have covered measles, or even the outbreak in Texas, so please read below for more information:

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The outbreak in Texas has grown to nearly 140 confirmed cases since the article I wrote on February 18, 2025, and has crossed state and county lines into Rockwall county, TX and New Mexico.

58 confirmed cases are now 133 and this is expected to grow in real time. In 9 days, measles cases in this ongoing outbreak have MORE than doubled.

All but 5 of these cases are among unvaccinated individuals. 80% of the measles cases are among kids — under 18 years old.

And now, a child has died from measles, the first measles death in the US in a decade.

This was an entirely preventable tragedy. We have had safe and effective vaccines to protect against measles infection, illness, complications, and death for OVER 60 years.

Why have we had no measles deaths in a decade?

Because we had measles under control in the US with widespread vaccination coverage. Measles is the most contagious human pathogen and we need 95% of the population to be vaccinated to keep it at bay if it gets into our communities.

But because of decades of anti-vaccine rhetoric from RFK Jr (I cannot overstate the deadly hypocrisy of him being the Secretary of HHS at this moment) and his allies, vaccine rate have dropped in the US continuously over the last 15 years.

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To be clear: this measles outbreak is not a result of him now being Secretary of HHS. This measles outbreak has to do with the fact that:

RFK Jr. has been spreading anti-vaccine lies since 1999.

Before Jenny McCarthy. Before Jim Carrey. Before Robert DeNiro. Before Joe Rogan.

This slow burn was built this over years off the back of his anti-science activism, spreading fear of “chemicals,” and making money off lawsuits going back through the 1980s.

In 2005, RFK Jr published an article in Rolling Stone and Salon called “Deadly Immunity” where he made widespread the false claims that vaccines caused autism and thimerosal was toxic.

This gave his lies national attention—it was also the official launch of Children’s Health Defense, his anti-science activist group that makes millions of dollars causing harm to people and our planet.

Now, Salon eventually retracted this and tried to “correct the record” but the damage was done, just like with the first lie that piqued RFK Jr.’s interest in this entire topic, the fraudulent study of Andrew Wakefield in 1998.

This long history of anti-science profiteering is why anyone with any understanding of history were horrified that not only was he nominated to head HHS, but that our elected officials — you know, the ones that are supposed to act in the interest of our citizens — confirmed him to that role.

RFK Jr. is HHS Secretary: Science, brace yourself.

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While you may feel like this is repetitive, there are too many people out here who do not know this history, so we need to keep repeating this over and over. Anyone who minimizes his role. Anyone who tries to suggest he cares about health. Any of your elected officials. This needs to be the new shot heard round the world.

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Let’s talk about our current situation, because while RFK Jr. got on a press conference yesterday and lied to the entire world, I’m here to correct the record.

Deaths due to measles in developed nations that have access to vaccines are not normal.

Measles vaccination is 97-99% effective at preventing infection and illness. That means death is also prevented. But to have that effect, we have to control the infections bit first. Without high vaccine coverage, we are leaving our populations vulnerable.

Measles kills 1 in every 1,000 people it infects.

The mortality rate varies depending on access to supportive care — because measles complications lead first to hospitalization requiring respiratory, cardiovascular, and neurological supportive care. If someone can survive through that with the resources they have available, they may survive.

In developing nations, mortality rate due to measles can be up to 10% without that supportive care access.

With vaccines in developed nations like the US, deaths due to measles should never be happening. That’s especially true when we eliminated measles as an endemic disease 25 years ago. But we are at serious risk of losing that status, and fast.

Approved measles vaccines have never caused a death.

A lot of people who circulate anti-vaccine rhetoric claim that the risk/benefit math doesn’t make sense because vaccines lead to adverse events.

Well, I’m going to set that straight too: the MMR vaccine in its tested, regulated, and approved formulation is incredibly safe and effective.

• The MMR vaccine has never been directly linked to a death.

• It ALSO prevents all of those deaths that are caused by measles—by preventing measles.

Even serious adverse events like anaphylaxis allergic reactions are incredibly rare (occurring in less than 1 in 1,000,000 vaccine doses administered) and those are treatable.

There have been rare instances where a vaccine was administered improperly and that itself caused a fatality. This has been documented in a few countries like Samoa and Syria where a healthcare provider wrongly added muscle relaxer as a diluent. The injection of the muscle relaxer—not the vaccine—led to those deaths.

While tragic, these are not related to the MMR vaccine itself.

Now, this happened in Samoa in 2018. RFK Jr. knew this and the circumstances of those deaths. Those nurses were prosecuted as well. Yet, instead of providing actual factual context, he used that medical error to lie about the MMR vaccine itself, which exacerbated a measles outbreak that led to the 83 deaths, primarily in children.

He played a direct role in preventable illness and death there, too.

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Measles cases require hospitalization when illness is severe, not for quarantine purposes.

In the current outbreak in Texas, at least 18 people are currently hospitalized, accounting for 13.5% of all currently reported measles cases.

RFK Jr said yesterday they were hospitalized for quarantine purposes. This is false.

These people are hospitalized because they have developed:

• respiratory distress or failure

• pneumonia

• dangerously high fever

• encephalitis

• severe dehydration due to vomiting and diarrhea

Guess what? These are all a result of measles. Measles is not a mild illness. And these illnesses are preventable.

I don’t want to only focus on the tragic situation, so let’s move into action items.

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If you’re unvaccinated, getting vaccinated now is a great idea. But it won’t provide instant protection.

One thing that has started to happen is people who have never gotten the MMR vaccine (or other vaccines) are getting vaccinated. That’s great. We need people to move back into reality — and while this is not the way I’d like for that to happen, I hope it is a lesson learned for some.

Just remember: vaccination does not provide instant protection. It takes around 2 weeks for your memory immune system defenses to develop in order to fend off exposure to the measles virus. In addition, the incubation period of measles is long.

Measles cases we are seeing now were infected several weeks ago.

MeV has a long incubation period, an average of 12 days (range 7-14 days). Initial symptoms are fever (as high as 105F), cough, runny nose, and conjunctivitis. Koplik spots (whitish-blue spots inside the lips and cheeks) also appear. The measles rash appears 2-4 days after: a flat red rash that starts at the hairline, spreads down the face, neck, torso, and extremities. People are contagious starting about 4 days before the rash appears (often when only early symptoms present).

This long incubation period means people may expose others before they know they have measles, contributing to viral spread.

That means we will see more cases even as people are getting vaccinated—this does not mean vaccines don’t work. It means those people got vaccinated too late relative to their exposure.

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If you don’t know if you’ve been vaccinated, try to track down your vaccine records.

If you do not have written documentation of MMR vaccine, you should get vaccinated.

Now, you can get measles antibody titers done to see if you have evidence of immunity before that, but some insurance companies won’t cover that and the testing also can take some time. The MMR vaccine is safe, and there is no harm in getting another dose if you may already be immune to measles, mumps, or rubella.

(this is true for vaccines, broadly—I got an additional HPV vaccine dose in my late twenties because I could not track down my vaccine records from when I was in college—the period that the HPV vaccine was first approved)

If you were born after 1957 and vaccinated prior to 1968, you should get an MMR vaccine.

The first measles vaccine that was approved in 1963 was an inactivated measles vaccine. This induces a less robust immune response, and it eventually was replaced with the attenuated version we use today. But if you were vaccinated between 1963 and 1967, you received the inactivated version. The waning immunity after 60 years plus your age places you at high risk for complications, so at least one dose of MMR vaccine is a good idea.

If you don’t know which vaccine you received and you were vaccinated in the 1960s, you should also get at least one dose of MMR.

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Should I get an MMR dose if I am an adult and was vaccinated as a kid?

Broadly speaking, if you got vaccinated as a kid, it is unlikely you’ll get infected even if you are exposed. Vaccination with the current 2-dose series is 97% effective. About 5% of people do not develop protection after the first dose (why the second dose was added in the 1980s), but 95% of those (meaning 97% total population) will be fully protected after a second dose.

There are simply some people who don’t develop long-term immunity after vaccination. There was a high-profile instance in 2011 of a vaccinated individual being ‘patient zero’ - Out of 88 close contacts, 4 got infected and had symptoms. Those who got infected had more than 200 contacts, and none got measles. (thankfully, vaccine coverage protected the vast majority of these people), but this is the exception, not the rule. And MMR vaccine rates have been in decline - which means these exposures will lead to continued spread, compared to this instance where transmission was halted pretty rapidly.

You do not need the MMR vaccine if you meet any of these criteria for presumptive evidence of immunity:

• You have written documentation of adequate vaccination:

  • If you’ve gotten at least one dose of an MMR or MMRV vaccine on or after the first birthday for preschool-age children (kids too young to get the second dose) or if you’re now an adult not at high risk for exposure and transmission.

  • OR (preferably) you’ve gotten 2 doses of an MMR or MMRV vaccine for everyone else, especially during ongoing outbreaks.

• You have laboratory confirmation of past infection or had blood tests that show you are immune to measles, mumps, and rubella.

• You were born before 1957. If you were born prior to 1957, measles rates were so high that is it presumed everyone either got measles and is immune, or was exposed to measles and developed immunity without becoming symptomatic.

If you have evidence of MMR vaccination but still want to get an MMR vaccine dose, that is absolutely safe.

In fact, some people at high risk for exposure, like healthcare workers or those who work within these communities or communities with low vaccine rates may already be opting for this as a protective measure.

I have been doing a lot of work travel and have a lot of upcoming work travel, so I also plan to get another MMR dose within the next week. In my case, while I likely have protection, I don’t want to take the time to get titers done and this will give me some additional peace of mind for my own health and those around me.

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Do you need to talk to your doctor about getting MMR vaccine?

There are some people who medically cannot get the measles vaccine, so contraindications apply for specific individuals who may be immunocompromised and as such, you should have a conversation with your medical team who know your health history before heading to the pharmacy.

If you have a weakened immune system due to disease (cancer, HIV/AIDS (if unmanaged, HIV-positivity alone does not preclude vaccination), tuberculosis) or medical treatments (such as radiation, immunotherapy, steroids, or chemotherapy), or you live with people who have the same. If you have blood conditions such as bruising or bleeding disorders you may also be precluded.

There are some reasons why people may need to delay MMR or adjust the schedule (although people should be vaccinated as kids!):

• If you’re pregnant or thinks you might be pregnant. You should wait to get MMR vaccine until after pregnancy has ended. You can get the MMR vaccine if you’re nursing though - and those antibodies will be passively transferred through breast milk.

• If you’ve gotten a blood transfusion or received blood products, you should delay vaccination by 3 months.

• If you received other vaccines in the previous 4 weeks. You can receive the MMR vaccine at the same time as others, but if your immune system is already working to develop protection against a recent vaccine not co-administered, the robustness of the MMR protection may be reduced.

• If you’re moderately or severely ill, you should delay until you’re feeling better (that’s true with all vaccines).

If you fit into these categories are you are near any of the reported cases or outbreaks (yes, there was also a potential exposure at LAX airport), talk with your physician about whether there are accommodations to be made if you want to get vaccinated.

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If you think you’ve been exposed to measles or have developed symptoms, there are things you can do.

With prompt medical attention, you can lessen the severity of illness even if you were unwittingly exposed.

There are state-by-state guidance for measles containment, but broadly they involve isolation of sick individuals, quarantine of any potential exposed individuals, and post-exposure prophylaxis within days of potential exposure.

• Anyone with measles rash much be in isolation for 4 days after the rash presents.

• Anyone with potential exposure to measles that is not vaccinated (or considered non-immune) must be in airborne quarantine beginning 5 days after the first potential exposure and last for 21 days.

• Post-exposure prophylaxis should be administered to any susceptible individuals: either the MMR vaccine within 72 hours of initial measles exposure OR therapeutic immunoglobulin (IG) within six days of exposure.

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Anti-vaccine disinformation is a top 10 global health threat.

This outbreak should illustrate this plainly. But if you know someone who is hesitant or resistant to the MMR vaccine, please send them my way; I’d be happy to address legitimate concerns.

Beyond that:

RFK Jr. is a liar who is endangering all of us.

He needs to be called out at every single turn. Every single person who hears information from him needs to know that he has been a liar for 30+ years, is still lying, and will continue to lie as the face of our leading health agency.

We cannot be polite about this anymore. It has not done anything to quell the loud voices that spread dangerous lies, and now, more than ever, we must feel a sense of urgency to stop that.

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Now, more than ever, we all must join in the fight for science.

Thank you for supporting evidence-based science communication. With outbreaks of preventable diseases, refusal of evidence-based medical interventions, propagation of pseudoscience by prominent public “personalities”, it’s needed now more than ever.

More science education, less disinformation.

- Andrea

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ImmunoLogic is written by Dr. Andrea Love, PhD - immunologist and microbiologist. She works full-time in life sciences biotech and has had a lifelong passion for closing the science literacy gap and combating pseudoscience and health misinformation as far back as her childhood. This newsletter and her science communication on her social media pages are born from that passion. Follow on Instagram, Threads, Twitter, and Facebook, or support the newsletter by subscribing below: