Study findings support the hepatitis B vaccine birth dose over other strategies
Mary Van Beusekom, MSToday at 9:57 a.m.
Hepatitis
Childhood Vaccines
Two new studies underscore the importance of the hepatitis B virus (HBV) vaccine birth dose, with a US study predicting that dropping or delaying initial vaccination would drive up chronic infections and an Ethiopian study finding lower mother-to-child transmission (MTCT) with birth-dose receipt.
After US Health and Human Services (HHS) Secretary Robert F. Kennedy Jr. panned the first study, as well as the New York Times’ coverage of it, on X, experts quickly pointed out deficiencies in his objections.
Shared decision making may lead to 83% more chronic infections
For the US study, the Massachusetts General Hospital–led team used published data to predict maternal HBV prevalence and hepatitis B surface antigen [HBsAg] testing, childhood vaccination completion, and age-stratified risk of chronic HBV infection. The study was published this week in the Annals of Internal Medicine.The impetus was the December 2025 recommendation from the Centers for Disease Control and Prevention’s (CDC’s) Advisory Committee on Immunization Practices (ACIP) that, rather than giving infants a dose within 24 hours of birth, parents engage in shared clinical decision making with their physician.
“In its deliberations, the ACIP did not identify any new or existing evidence of vaccine harm or toxicity and maintained recommendations for birth-dose HBV vaccination for newborns of women diagnosed with HBV infection or with unknown HBsAg status at the time of delivery,” the authors wrote.
The next month, over the objections of physicians and medical organizations, the CDC announced changes to the entire childhood vaccine schedule and recommended the HBV vaccine only for certain high-risk groups and based on shared decision making rather than universal vaccination.
“The objective of this modeling study was to examine the potential effect of recent federal changes to HBV vaccination policy, should they be implemented, on HBV infections and HBV susceptibility in U.S.-born children up to age 20 years,” the researchers wrote.
They modeled 3.6 million annual births under three HBV vaccination strategies: universal birth-dose vaccination, deferred (two-month) vaccination of infants born to uninfected mothers without HBV infection, and shared decision making for two-month vaccination of infants of uninfected mothers.
The researchers estimated that the universal birth-dose strategy would result in 255 chronic HBV infections per 3.6 million children after 20 years. The deferred strategy would lead to 303 chronic HBV infections, a 19% increase over the universal birth-dose strategy. And shared decision making would result in 467 chronic HBV infections, an 83% increase over the universal birth dose.
The estimated number of resolved HBV infections after 20 years would be 223 with the universal birth dose, 444 with the deferred strategy, and 1,632 under shared decision making. After 20 years, 232,200 people would be susceptible to HBV infection with the universal birth-dose, 474,000 with the deferred strategy, and 1.8 million under shared decision making. The increased risk of adulthood HBV infections is important, because later-in-life infections are more likely to lead to life-threatening conditions such as liver failure, the authors said.
“In our assessment of model validity, the 255 chronic HBV infections projected with the universal birth-dose strategy was similar to CDC estimates (up to 267 infections in children),” they wrote. “Similarly, the universal birth-dose strategy would result in 92.2% of people completing the HBV vaccination series before age 20 years, which is equivalent to 2024 population estimates.”
In a Brigham and Women’s Hospital news release, lead author Amir Mohareb, MD, at Mass General Brigham, said, "These findings show why policy makers should re-implement recommendations for universal hepatitis B vaccination at birth. Even a small increase in childhood HBV infections could have large clinical, public health, and economic effects.”
Kennedy objects to study design, methods
In his comments on the study on X, Kennedy said, “The paper they [New York Times] discuss is a “modeling study” or simulation based on assumptions, not a study of evidence or outcomes.” He added that the Times should issue a correction.The secretary is asking a modeling study for a standard of evidence he never asked of his own committee.
Jake Scott, MD
But Jake Scott, MD, a clinical associate professor specializing in infectious diseases at Stanford Medicine, takes issue with that.
“The secretary is asking a modeling study for a standard of evidence he never asked of his own committee,” he told CIDRAP News. “They reversed 34 years of policy in December without a single new piece of safety data, and now that someone has put numbers on what that decision costs, the numbers are the problem. You cannot run this experiment on newborns, so you model it. He knows that. What he objects to is the answer.”
Modeling, Scott said, is how every vaccine policy change gets evaluated before the fact, because it would be unethical to randomly assign newborns to a delayed hepatitis B dose and wait 20 years to count the cases of cirrhosis and liver cancer.
“This model was built from published epidemiologic data and checked against CDC's own estimates of pediatric infections,” he said. “Calling it a simulation does not make its inputs any less real. A modeling estimate of roughly 1,400 additional chronic infections a year was already public before ACIP's December vote. The committee voted anyway.”
Kennedy said that he “rejects the idea that respecting parents’ choices means abandoning children’s health. Under my leadership, HHS puts informed consent, individual medical circumstances, and conversations between parents and doctors at the center of health decisions.”
On X, Vincent Iannelli, MD, a Texas pediatrician, responded, ”You can't promote informed consent when you constantly push misinformation and propaganda about vaccines, which scares parents away from getting vaccinated.”
Birth dose plus maternal antiviral prophylaxis
For the Ethiopian study, published in Clinical Infectious Diseases, a team led by researchers in Addis Ababa conducted a multicenter study from May 2022 to June 2024. The authors identified mothers who tested positive for HBsAg during pregnancy and evaluated mother-infant pairs six to 12 months postpartum for HBV MTCT. They also stratified the effectiveness of the birth dose by maternal risk profile.MTCT is an important route of new HBV infections, the authors said. “In Africa, limited and conflicting data on the effectiveness of hepatitis B birth dose vaccination (HepB-BD) have contributed to fragmented adoption and sub-optimal implementation,” they wrote.
The analysis included 387 children born to HBV-positive, HIV-negative mothers who had completed routine HBV vaccination. The median age at infant testing was 10 months.
Overall, MTCT risk was 5.2%. MTCT was significantly lower among infants receiving the HBV birth dose alone (0%), compared with those with no immunoprophylaxis (administering immunoglobulin to prevent infection) at birth (15.3%).
No transmission occurred with the birth dose plus hepatitis B immunoglobulin (0%). An elevated maternal viral load (adjusted odds ratio [aOR], 16.6) and hepatitis B e-antigen (HBeAg) positivity (aOR, 4.21) were tied to increased MTCT risk in infants without immunoprophylaxis at birth.
The authors said that the HBV birth dose is highly effective in reducing MTCT and should be prioritized for scale-up in Africa. “In Ethiopia, the current vaccination series starting at 6 weeks is insufficient to prevent HBV MTCT,” they concluded.
In a commentary in the same journal, Anna Lok, MD, of the University of Michigan at Ann Arbor, MD, said that “public health communities should advocate for optimal MTCT prevention including HepB-BD and maternal antiviral prophylaxis based on HBV DNA testing to protect future generations in Africa.”