They're About to Vote on Your Kids' Vaccines

MMRV, hepatitis B birth dose, COVID vaccines—will you still have access to them?

You remember that feeling in high school when you had a big test coming up and you prepared your head off, but still had a queasy feeling all week like you drank expired milk? That's the feeling we've had all week in anticipation of the upcoming ACIP meeting. Unfortunately, many of us are nervous because we fear we already know the outcome— like walking into an exam knowing the teacher has already decided to fail half the class. Pass the Pepto.

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The Advisory Committee on Immunization Practices (ACIP) meets September 18-19, and based on the agenda, three vaccines are under scrutiny: MMRV (the combo measles-mumps-rubella-varicella shot), hepatitis B birth dose, and COVID-19 vaccines. Making matters more complex, Secretary Kennedy announced five new ACIP member appointments just today, bringing his total hand-picked appointments to 13 members since June (though one withdrew due to a conflict of interest). This rapid reshaping of the committee, which typically takes months or years, adds another layer of uncertainty. We don’t know a whole lot about the dozen folks who will literally be critical to determining our access (and our kids’ access) to these lifesaving vaccines.

For the full technical analysis with all citations, check out the briefing that several of us contributed to over at The Evidence Collective. But if you mainly want the nuts and bolts, let’s discuss…

The MMRV Vaccine and Febrile Seizures

Febrile seizures are seizures that can happen naturally when young children get fevers, and they can be scary to witness. They don't cause long-term problems, and kids are typically fine afterward, but that doesn't make them less frightening in the moment.

Very rarely, febrile seizures can occur after the first MMR dose (MMR is the vaccine that protects against measles, mumps, and rubella.). The ACIP committee may reconsider MMRV recommendations based on the risk of febrile seizures, potentially claiming this information was previously "concealed." This is puzzling because we've openly discussed this risk since 2009. About 1 in 3,000 children may have a febrile seizure after their first MMR vaccine. With MMRV, it's slightly higher—about 1 additional seizure per 2,300-2,600 children. Parents receive this information on the official vaccine information sheet, and the CDC already recommends giving MMR and the varicella vaccines separately for the first dose unless families prefer the combo. This lowers the risk of febrile seizures compared to MMRV. Again, these don’t cause long-term problems.

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What often gets lost in this discussion is that by age 4-6, when kids get their second dose, there's no increased risk because most children have outgrown febrile seizures. So, families may choose MMRV at this age because, honestly, who wants to put their kid through two shots when one will do?

If the ACIP committee decides to restrict MMRV, we're looking at potential vaccine shortages during the worst measles outbreak in decades for babies at risk of complications from measles. We're also taking away parents' choice—ironically, at a time when medical freedom is supposedly valued. More shots mean more tears, more time off work, and historically, more kids who don't complete their vaccine series. This puts both kids and the broader health of the public at risk.

Hepatitis B Vaccine at Birth

We understand why parents question this one. Your baby was just born, perfect and healthy, and suddenly they're talking about a vaccine for something transmitted through blood and bodily fluids. "My baby isn't shooting up drugs or having sex," you might think. It's a fair point that deserves a real answer, not a dismissive one.

As we write this, NPR is reporting that ACIP is expected to vote on delaying the hepatitis B vaccine until age 4. Currently, it’s recommended to start at birth and complete the 3-dose series by 18 months. This would be a dramatic departure from 30+ years of successful policy. Yes, the most common transmission routes in adults are IV drug use and sex—but that's not how kids get infected. Infants commonly get infected during childbirth, when a mother’s blood can pass to the baby. Without preventive medical treatment (which includes the vaccine right after birth), 70-90% of babies born to infected mothers will get infected themselves. And 90% of babies infected through childbirth will develop a chronic, lifelong, and often debilitating form of Hepatitis B. Children get hepatitis B through other routes, including contact with infected household members who may be unaware of their infection, from bites at daycare that break the skin, or from sharing personal items like toothbrushes. The virus can survive for a week on surfaces, meaning children can be exposed in ways we don’t expect. Waiting until age 4 means four years of vulnerability during the time when infection is most likely to become chronic and cause lifelong liver damage.

As part of an ongoing series through our non-profit, The Center for Unbiased Science and Health, we're having conversations with folks who have changed their perspective on vaccines over time, and we want to share their stories.

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Yesterday, we shared the story of one mom who was convinced that giving her baby the HepB vaccine was unnecessary because they weren't "high-risk", so when her baby was born she refused the HepB shot. Two weeks later, her son's father became violently ill. Turns out he'd been carrying the hepatitis B virus his entire life. He was born with it and never knew. The mom had to get tested and discovered she had also been infected at some point without knowing it. They were both infected but had no symptoms. Her baby had been exposed from day one, and suddenly she realized how close he'd come to disaster.

Fortunately, the mom changed her mind and started the vaccine series shortly after her son was born—protecting him from what could have been a lifetime of liver disease.

When babies get infected at birth, 90% go on to develop chronic infection that silently damages their liver for years, potentially leading to cirrhosis, liver cancer, or even death. Before we started vaccinating, 18,000 U.S. kids got hepatitis B annually by age 10, and half had no idea how they got it. The virus can survive on surfaces for a week and spread through invisible amounts of blood, not just from infected fathers who don't know they have it, but anywhere.

Now, you might say, "But we screen moms during pregnancy!" True, and while 88% of insured women get properly screened, that still leaves significant gaps—and it's worse for those on Medicaid. If screening has occurred, the risk of a false negative is generally low, but the cost of a false negative is catastrophic, and the vaccine has an excellent safety record. Plus, lab results can be lost or misinterpreted, and moms can get infected between screening and delivery. Even when we catch an infected mom, only about half the babies get properly treated.

The vaccines themselves (Engerix-B and Recombivax HB) have an excellent safety record. The only confirmed risk is allergic reactions at 1 in 600,000 doses. All those scary claims about SIDS? Studied repeatedly and disproven.

Public health makes population-level recommendations to catch those rare but catastrophic cases. If your family has good prenatal care and low risk factors, your individual risk is indeed very low, and ultimately, the decision is always up to you as the parent. But for the babies who slip through the cracks? This vaccine is literally life-saving. It has prevented an estimated 22 million deaths globally. This is why leaving access to the birth dose is so important. Delaying that dose may mean some at-risk babies never get the needed protection.

COVID Vaccines and VAERS Reports

Last week, the Washington Post leaked that ACIP may present 25 pediatric death reports from VAERS as evidence against COVID vaccines. This is where things get tricky, because understanding VAERS requires understanding how vaccine safety monitoring actually works.

Think of VAERS like a community suggestion box. Anyone can drop in a report (in fact, healthcare providers are legally required to report certain events to VAERS, including serious adverse events and deaths following vaccination that occur within a specified time period after vaccination). The system is designed to catch patterns, not determine causation. The CDC explicitly states that "reports of death to VAERS following vaccination do not necessarily mean the vaccine caused the death."

This suggestion box approach actually works brilliantly. VAERS caught the J&J blood clots (leading to 9 confirmed deaths and the vaccine being pulled). It caught myocarditis in young males (about 100 per million doses after the second shot) after being flagged internationally, which led to updated spacing recommendations that reduced the risk. It is designed to be an alarm system. The system works exactly as designed.

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But raw VAERS reports aren't conclusions. When someone reports a serious event, it triggers investigation through systems that can actually determine causation—the Vaccine Safety Datalink analyzes medical records from 9 million people, while the FDA's BEST System monitors electronic health records from millions more.

Parents rightfully worry about myocarditis, especially in teenage boys. It's real, and it's scary to think about your kid having inflammation of the heart muscle. But context matters: COVID itself causes myocarditis more often and more severely at higher rates than the COVID vaccine. So, your child is much more likely to develop myocarditis after having COVID than getting the vaccine! More importantly, data presented at the April 2025 ACIP meeting shows that with the updated vaccines and current recommendations, this risk has largely disappeared—we saw it with the primary series in 2021-2022, but it's virtually absent now. When we discovered this risk, we didn't hide it; we were transparent about it while emphasizing that the benefits of vaccination still far outweighed this small risk. The fact that this signal has now mostly disappeared shows that the system is continuously monitoring and improving.

Meanwhile, in one CDC analysis of 25 pediatric COVID deaths, 14 of the 16 kids old enough for vaccination were unvaccinated. None were up-to-date. The vaccines reduce emergency visits and hospitalizations and are associated with a lower risk of long COVID in both kids and adults.

There’s a lot at stake. If ACIP restricts COVID vaccine recommendations to only certain high-risk groups, it doesn't just affect those outside the groups. Politicians might say "anyone who wants one can get one," but that's not how our healthcare system works. Without an ACIP recommendation, insurance companies often won't cover vaccines. You may need a prescription for off-label use. If the ACIP says certain groups should not receive the vaccine, doctors or pharmacists may stop stocking them due to liability concerns. Your access to protect your family becomes a matter of whether you can afford to pay out of pocket, turning a public health tool into a luxury good.

Why This Week Matters

Beyond individual vaccines, this ACIP meeting represents something larger. For decades, ACIP has used systematic frameworks called GRADE and EtR to evaluate evidence transparently. These aren't just bureaucratic processes; they're guardrails ensuring decisions are based on all the evidence, not cherry-picked data.

When these frameworks get abandoned, as happened in June, we lose that protection. The rapid appointment of new members in what typically takes years raises the question: Are we watching science-based decision-making or political theater?

During the meeting, watch for these red flags: claiming correlation proves causation ("autism rates rose with vaccine use"), cherry-picking one flawed study while ignoring dozens of good ones, or moving goalposts—when one concern is addressed, immediately pivoting to a new one without acknowledging the previous claim was wrong.

The Bottom Line

Every medical intervention has risks. Always has, always will. The question isn't whether vaccines have risks—it's whether those risks are worth the benefits. For decades, ACIP has made these calculations transparently, adjusting when new evidence emerges.

What we're watching for this week is whether that tradition continues or whether decisions will be based on selective data and predetermined conclusions. Your family's access to vaccines—and your freedom to choose them—may hang in the balance.

You don't have to pick a "side" in the vaccine debate to want transparent, evidence-based processes. We all deserve committee members who evaluate evidence fairly, acknowledge both benefits and risks honestly, and make recommendations based on data rather than ideology.

Stay informed. Ask hard questions. And remember that behind all the politics and proceedings are real families—maybe yours—trying to make the best health decisions they can with the information they have.

Stay Curious,

Unbiased Science (and friends!)

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