Is the MMR a Leaky Vaccine?

According to Robert F. Kennedy, Jr, the MMR vaccine is a ‘leaky’ vaccine.

Wait, what?

Kennedy’s Leaky Vaccine Theory

While I’m sure you know that Kennedy is wrong and the MMR is not “leaky,” let’s see what he means…

In a recent interview with NBC News, Robert F. Kennedy, Jr. said that:

“One of the problems with the current vaccines is that it is a leaky vaccine, so the immunity you get is ephemeral. And it wears off over time. It’s much more likely that older people will get it and also, this is the most frightening thing about it, it does not provide maternal immunity. It used to be that a mother who had gotten measles as a child, her child who she was breastfeeding, would be immune from measles for at least the first year of their lives. That’s a very dangerous time to get measles, so you want them to be immune. But we now know that the vaccine does not provide maternal immunity to those children, so those children are now unprotected and as the vaccinated population gets older, that is going to be a problem that gets worse and worse.”

Robert F. Kennedy, Jr.

As usual, everything he said was very wrong…

But before we get into that, let’s see how he ended the interview!

When asked “for America’s children right now, do you recommend they take the MMR vaccine?,” what do you think he said?

“I’m not gonna—,” he said.

RFK Jr. is courting Black voters, a group he once targeted with vaccine disinformation

He then walked away!

His misinformation about vaccines has likely helped put us in a situation in which measles rates are rising and vaccination rates have dropped, and he, a candidate for President of the United States, walks away when asked how parents should protect their children.

What Kennedy Gets Wrong About the MMR Vaccine

Of course, it’s no surprise to you that Kennedy didn’t say that parents should vaccinate and protect their kids with the MMR vaccine if you know anything about his views on vaccines.

Remember, this is the guy who has said that their are deadly new rogue strains of measles that have mutated and have been spreading like wildfire and causing worldwide outbreaks because the MMR doesn’t cover them.

This is also the guy who thinks vaccines are associated with autism.

Is the MMR a Leaky Vaccine?

But what does it mean if a vaccine is “leaky?”

“There is a theoretical expectation that some types of vaccines could prompt the evolution of more virulent (“hotter”) pathogens. This idea follows from the notion that natural selection removes pathogen strains that are so “hot” that they kill their hosts and, therefore, themselves. Vaccines that let the hosts survive but do not prevent the spread of the pathogen relax this selection, allowing the evolution of hotter pathogens to occur. This type of vaccine is often called a leaky vaccine. When vaccines prevent transmission, as is the case for nearly all vaccines used in humans, this type of evolution towards increased virulence is blocked. But when vaccines leak, allowing at least some pathogen transmission, they could create the ecological conditions that would allow hot strains to emerge and persist.”

Imperfect Vaccination Can Enhance the Transmission of Highly Virulent Pathogens

So “leaky” vaccines might actually be a thing!

A theoretical thing…

It certainly doesn’t apply to the MMR vaccine though, which provides nearly 98% protection after two doses – protection which doesn’t seem to wane or wear off, which means that you don’t need a booster dose when you get older.

After all, very few fully vaccinated adults or seniors get measles during an outbreak. And they typically don’t die if they do get sick. Most measles deaths are in those who are unvaccinated.

In Samoa, for example, 87% of the measles deaths were in children under age 5!

And although it might be a little shorter than natural protection (8 vs 12 months), the MMR vaccine also protects infants (a process called passive immunity, not maternal immunity) whose mothers were vaccinated. And it does it without the high cost of those mothers having to survive a natural measles infection!

So, not surprisingly, Kennedy once again gets everything wrong when talking about vaccines and vaccine preventable diseases.

Well, almost everything…

At least he admitted that it is dangerous to get measles!

More on Kennedy’s Leaky Vaccine Theory

• Robert F Kennedy, Jr.’s Medical Racism
• Has Bobby Kennedy Taken Over the Anti-Vaccine Movement?
• Doing the Math on Kennedy, Vaccines and Mercury
• Bobby Kennedy’s Vaccine Injury Debate
• Did Bobby Kennedy Admit That Chickenpox Kills People?
• Anti-Vaccine Groups Are Still Targeting Minority Communities
• Imperfect Vaccination Can Enhance the Transmission of Highly Virulent Pathogens
• Maternally derived measles immunity in children of naturally infected and vaccinated mothers
• RFK Jr. is courting Black voters, a group he once targeted with vaccine disinformation
• RFK Jr. Is Our Brother and Uncle. He’s Tragically Wrong About Vaccines.
• Fact-checking Presidential Candidate Robert F. Kennedy, Jr., on Vaccines, Autism, and Covid-19
• RFK Jr. Super-PAC Puts Promoters of Conspiracy Theories on the Payroll
• RFK Jr. spent years stoking fear and mistrust of vaccines. These people were hurt by his work
• A Pro-Vaccine Documentary that Tackles Vaccine Hesitancy