A comprehensive review of the medical literature supports the longstanding practice of administering the hepatitis B vaccine to all medically stable infants at birth. The study, published in Pediatrics, found no evidence to justify new guidance issued last year by the CDC’s Advisory Committee on Immunization Practices (ACIP) discouraging the birth dose for infants born to mothers who test negative for hepatitis B during pregnancy.

The review was conducted by researchers with the Vaccine Integrity Project of the Center for Infectious Disease Research and Policy (CIDRAP) at the University of Minnesota, Minneapolis.

“We did not identify any new evidence that would suggest that there is a concern about safety of the hepatitis birth dose,” said Angela Ulrich, PhD, MPH, an infectious disease epidemiologist and researcher with CIDRAP, who led the review. “We also didn’t see any concerns about effectiveness, or that safety or effectiveness would improve if that birth dose was delayed or deferred.”

Since 1991, the CDC had recommended screening for hepatitis B virus (HBV) during pregnancy and giving hepatitis B vaccination to all medically stable infants at birth. In 2025, the Department of Health and Human Services (HSS) Secretary Robert F. Kennedy Jr replaced all 17 ACIP members. The new group voted in December to allow women who screen negative during pregnancy to decide, in consultation with their providers, when or if to vaccinate their child for hepatitis B; and if not at birth, then no earlier than 2 months of age. The committee also suggested considering collecting infant immune titers to guide decision-making for completing the vaccine series.

The panel justified its decision on the grounds that rates of perinatal transmission of hepatitis B in the US are “very low” and that screening for the infection “identifies nearly all hepatitis B infections during pregnancy,” among other rationales.

Kennedy has long questioned the safety and efficacy of the newborn dose, claiming without evidence the thimerosal preservative in the shot causes autism. Last month, Kennedy called the US a “high outlier” in the number of immunizations recommended for all children. Kennedy has also pushed for a clinical trial of the vaccine in Guinea-Bissou, where hepatitis B is rampant. That study has been paused for an ethics review.

The CIDRAP team conducted a comprehensive review of evidence of the safety, immunogenicity, and efficacy of the birth dose, a delayed first dose, and the potential role of serology for clinical decision-making. They analyzed numerous sources, including studies of the epidemiology of hepatitis B infection, clinical trials, systematic reviews, vaccine safety data from surveillance and clinical studies, and the potential effect of revised guidelines on individual and public health. Additionally, they reviewed the history of ACIP recommendations and resulting trends in hepatitis B incidence.

Since universal vaccination recommendations were initiated in 1991, the incidence of pediatric infection with the HBV has declined by approximately 99%, the researchers found. The incidence of acute hepatitis B infection has decreased substantially over the past four decades, from an estimated peak of 1 million to 1.25 million cases per year in 1985 to an estimated 14,400 annual cases in 2023, the researchers said. In 2022, there were no reported cases in 1- to 4-year-olds and only two cases in 5- to 14-year-olds, they noted.

In additional findings:

• National surveillance systems since 2018 have reported fewer than 20 perinatal cases annually.
• The vaccine is safe and well-tolerated in all age groups, with only mild-to-moderate short-term reactions such as redness and swelling at the injection site.
• In infants born to women with HBV, hepatitis B vaccination at birth, along with hepatitis B immune globulin, reduces the risk for transmission by 83%-97%.
• Seroprotection increases with each vaccine dose in the series. Approximately 25% of healthy infants seroconvert after the first dose, 63% after two doses, and 95% after the third dose, indicating that completing the three-dose series confers optimal protection.
• Searches found no studies investigating the long-term protective effects of an incomplete vs complete hepatitis B vaccination series, and no studies evaluating whether anti-HBs titers collected after the first or second doses in infants could be used as a reliable indicator of short- or long-term protective immunity.

The researchers conducted the study to provide information to medical societies making recommendations, and to the public, about any new information available regarding the safety or effectiveness of the hepatitis B birth dose, Ulrich said.

With hepatitis B vaccines universally given to newborns, rates of the disease in kids plummeted, she said, “and we see that protection extend to adolescence and into early adulthood and beyond.” The recent ACIP reviews “did not report any new safety signals related to the hepatitis B vaccine nor evidence of improved protection from a delayed first dose,” Ulrich and colleagues wrote.

“These types of changes in recommendations are being done without full transparency by the current ACIP and by HHS,” Ulrich said. “We would point people back to these four decades’ worth of information and evidence that we have that the vaccine is remarkably safe and it has protected thousands of young kids from getting a lifelong illness.”

The American Academy of Pediatrics (AAP) continues to recommend routine hepatitis B vaccination for all newborns. Some medical centers, including Children’s Hospital of Philadelphia (CHOP), Philadelphia, and UC Davis Health, have posted information on the importance of continuing to provide these vaccines.

Joanna Parga-Belinkie, MD, told Medscape Medical News she applauds the AAP for publishing the paper.

“It’s a really comprehensive review of the hepatitis B vaccine, how past recommendations were made regarding the vaccine, and also the importance of still recommending the first dose, which the AAP does in their vaccine schedule,” said Parga-Belinkie, a clinical neonatologist at CHOP and an associate professor of clinical pediatrics at the Perelman School of Medicine, University of Pennsylvania, Philadelphia. Her hospital — and all others she is familiar with — have continued to offer the vaccines at birth.

Pediatricians are united about following the AAP schedule and really don’t feel like the changes were evidence-based, she said.

However, the revised guidance has been confusing for families, Parga-Belinkie said, and she is seeing more questions about the vaccine from parents as well as more parents declining the vaccine when it’s offered. She and colleagues are preparing a paper on refusals for hepatitis B vaccines they hope to publish soon.

This study was supported by the Alumbra Innovations Foundation. The interviewees reported having no relevant financial disclosures.