ACIP’s Reversal on Hepatitis B Birth Dose Raises Alarms Over Preventable Infections

As the CDC’s Advisory Committee on Immunization Practices (ACIP) moves to end its longstanding recommendation for universal hepatitis B vaccination at birth, experts warn the shift could undo decades of progress in preventing chronic infection, cirrhosis, and liver cancer. In an interview with Pharmacy Times, immunologist Morgan McSweeney, PhD, known online as Dr. Noc, explains the evidence behind the original birth-dose policy, why early immunization is uniquely effective, and what pharmacists should expect as the consequences of this policy change unfold over the coming decades.

Q: Can you summarize the evidence-based public health rationale for the longstanding recommendation of administering the hepatitis B vaccine at birth?

Morgan McSweeney, PhD: Something a lot of people don't understand about the hepatitis B vaccine is where the recommendation came from. And part of the reason for that, I think, is because it's been going on for decades at this point, for 4 decades-plus at this point, so we've started to forget a little bit how we got here in the first place. I think it's important to understand a little bit about the virus itself and how that led to the recommendation that all babies get the vaccine at birth.

So, the virus itself is, like many viruses, actually pretty sneaky. When you first get infected, whether that's at birth or later in life, probably you don't know that it's happened. It can happen from a microscopic amount of blood on a surface. It can be stable on that surface for a week or longer, and you can get infected. Of course, you can also get infected from birth if the mother happens to be hepatitis B-positive and doesn't know it. There's a lot of transfer of body fluids in the birth process. The baby can become infected, and you'll never know, perhaps until 30 years later or 40 years later, when that child gets liver cancer or cirrhosis because of that infection.

Unfortunately, it does take a long time for the effects to show up, and because that gap is so long, it's not like something is happening a week later, and you see, Oh my gosh, they're bleeding out of their ears. Something that would be kind of easier to respond to. It would be more salient that we need a vaccine for this thing, but when it's 30 years down the road that all these harms are happening, it becomes a little bit confusing. It's easy to say, like, well, my kids didn't get the vaccine. Nothing has happened to them yet. It seems totally fine.

So, the way we started in the United States, actually, was with a risk-based approach to vaccination. Initially, it was not all children getting the hepatitis B vaccine. We were trying to determine which mothers are at risk of transferring it to their child, for example, by test results, and then vaccinating children correspondingly. Unfortunately, that didn't work. There were still 10,000 to 20,000 children each year who were getting infected with hepatitis B, and then some fraction of those children were going on to develop liver cancer or cirrhosis later on. It's a pretty big fraction, actually.

This is the big reason why we care a lot about it happening at birth or in infants. If an infant is infected at birth with hepatitis B, there's a 90% risk that they're going to go on to develop a chronic infection. If an adult is infected later in life, there's a 5% risk of chronic infection, so it's a really big deal. Infants don't have the immune systems capable of fending off that chronic infection, and the result is that about 25% of those infants who get the infection go on to die from liver cancer or cirrhosis-related complications, so it's a really big deal that really young babies be protected. And when we were trying this risk-based system, trying to figure out which mothers are at risk of transferring it to their babies and so on, it just wasn't working. Tens of thousands of babies were getting infected, so we switched to universally recommending it for all babies, and that number dropped to almost zero, under 100 per year. And so that's what we've been doing ever since, with great success.

Q: From an immunologic standpoint, why is the birth dose specifically important in preventing perinatal transmission and early-life infection risks?

McSweeney: This is one of the cool things about hepatitis B vaccines, actually. For a lot of infections, like if you think of influenza or COVID-19, if you get infected on a Tuesday and you go get the vaccine on that Tuesday, the vaccine is not going to do anything to protect you, because it's such a short time period between when you're exposed to the virus and when it starts to manifest in respiratory disease in those cases. Hepatitis B is not like that. If a mother passes on hepatitis B to a child at birth, it actually takes a few weeks before that virus sets up this chronic infection in the liver, which means you actually do have enough time to give the child the vaccine right after birth. You've got that couple-week time window when the vaccine actually kicks in and does a pretty good job of fending off the odds of a chronic infection. And that's not due to some clever design of the vaccine; it's just the biology of the virus. It takes a long time before it sets up, so you do have this time window where you can vaccinate the child and they will be protected. You know, they're not going to have that 90% odds of chronic infection that could lead to liver cancer or cirrhosis. So that's the importance of giving the vaccine at birth. Obviously, if you wait 2 months to give the vaccine, or 2 years, or 12 years, obviously, by that point, the virus has had plenty of chances to establish a chronic infection in the liver.

Q: What immediate and long-term consequences should pharmacists be aware of now that the CDC Advisory Committee on Immunization Practices (ACIP) has removed their recommendation for the routine birth dose?

McSweeney: RFK Jr's vaccine panel's decision to remove the universal recommendation for the hepatitis B vaccine—I mean, there are very clear immediate and long-term consequences. Immediately, fewer children will get the vaccine, which means more children will get hepatitis B in the longer term. And I'm talking 20, 30, 40 years down the road; of those children who got hepatitis B, 90% of whom will have gone on to establish chronic hepatitis B infection, a quarter of them are going to get liver cancer or cirrhosis and die from related complications, like we were talking about before. Those 2 things are very far removed in their time scale, so you're not going to see a bunch of children dying next year because they didn't get vaccinated this year or even 5 years from now. This is going to happen decades in the future, and so that kind of removes a lot of the apparent consequences from the decision.

But we know very clearly what's going to happen, because we've already had 4 decades of experience showing that, in the reverse direction, when we introduced the vaccine, liver cancer and cirrhosis in younger adults went dramatically down. After that, these hepatitis B infections went dramatically down. There's some very good data out of China, which actually has a very similar vaccination program as the US, showing exactly that kids who got the hepatitis B vaccine have much lower rates of liver cancer and cirrhosis. And so now we're just going to see the exact opposite thing happen, which is tragic, because it's totally preventable. We know exactly what's going to happen.