New US Centers for Disease Control and Prevention (CDC) recommendations against universal birth-dose HBV vaccination will result in more newborn infections, deaths, and healthcare costs, according to two studies published yesterday in JAMA Pediatrics.

HBV infection at birth or during early infancy can lead to lifelong health problems such as chronic liver disease and liver cancer. Newborns are at highest risk, with 90% of those infected with HBV eventually developing chronic infections and 25% dying early from cirrhosis or liver cancer.

While prenatal screening for HBV has long been recommended, roughly 12% to 16% of pregnant women in the United States don’t get screened, leaving a substantial number of newborns at risk for undetected infection. 

In December 2025, without any evidence to support the move, the CDC’s Advisory Committee on Immunization Practices (ACIP) voted to replace the universal HBV vaccine birth-dose recommendation with shared clinical decision-making for infants born to HBV-negative mothers, advising routine birth doses only for newborns of HBV-positive or unscreened women. 

The CDC later accepted ACIP’s recommendations, although many pediatricians and medical societies say they will continue to vaccinate all newborns against HBV.

In addition, the CDC said that babies who don’t receive a birth dose of HBV vaccine shouldn’t receive one until they are at least two months old, again without supporting data. The CDC first recommended the birth dose in 1991, advising the receipt of two more doses before 18 months of age.

Targeted birth-dose may lead to 600-plus more cases

For the first study, a Boston University–led research team conducted a modeling study with a simulated US birth cohort of 3.7 million infants under both the former and current CDC HBV recommendations.

“Although the [ACIP] proposal would not alter recommendations for infants of unscreened mothers, historical data suggest that removing a universal birth-dose vaccine recommendation may reduce vaccination coverage in this group,” the study authors wrote.

With the current maternal HBV screening rate of 86%, the universal birth-dose vaccination recommendation led to a median of 1,292 newborn infections (95% percentile interval [PI], 670 to 2,228). 

In comparison, the targeted birth-dose vaccine recommendation was tied to the addition of another 628 (95% PI, 340 to 1,034) newborn infections when birth-dose uptake in the infants of unscreened mothers was 10% (mirroring historic coverage declines under a targeted recommendation) and 69 (95% PI, −32 to 190) more infections when coverage was 80% (mirroring levels under a universal recommendation.) 

Although the [ACIP] proposal would not alter recommendations for infants of unscreened mothers, historical data suggest that removing a universal birth-dose vaccine recommendation may reduce vaccination coverage in this group.

To offset the additional infections under the targeted birth-dose vaccine recommendation, more than 100,000 more pregnant women would need to be screened if birth-dose uptake among the newborns of unscreened mothers were 80% and more than 400,000 if coverage were 10%.

“Findings from this study indicate that the targeted birth-dose vaccine recommendation will likely increase neonatal infections unless maternal screening rises substantially or vaccination coverage among infants of unscreened mothers exceeds current levels,” the researchers wrote. “As historic data show such improvements are unlikely, these findings underscore the continued importance of universal screening and vaccination as complementary safeguards.”

In a Boston Medical Center (BMC) news release, senior author Rachel Epstein, MD, of BMC, said that even small declines in birth-dose vaccination can raise HBV risk—particularly for newborns of unscreened mothers. “This study highlights the importance of consistent prevention strategies to protect newborns and reduce hepatitis B nationwide,” she wrote.

Even brief delays in vaccination tied to lower completion rates

The second study, led by an Oregon Health & Science University researcher, estimated health outcomes and healthcare costs of delaying administration of the first HBV vaccine birth dose to age two months to 12 years in 3.6 million infants in a single US birth cohort. The infants were born to mothers who tested negative for HBV. The model of infections under eight different scenarios assessed economic costs from birth in 2025 up to 18 years.

All delayed vaccination scenarios resulted in more infections, worse health outcomes, and higher healthcare costs than when the first HBV birth dose was administered. Under perfect adherence, delaying HBV vaccination by two months for infants of mothers who tested negative for the virus resulted in another 90 (range, 16 to 107) acute infections, 76 (range, 14 to 97) chronic infections, 29 (range, 6 to 53) deaths, and an additional $16.4 million in costs for infants. 

Even brief delays in HepB vaccine initiation were associated with a substantial increase in HBV infections, adverse health outcomes, and health care costs.

Delaying the first dose to 12 years of age led to 190 (range, 61 to 233) more acute infections, 50 (range, 15 to 83) deaths, and nearly $30 million in additional costs. Delaying HPV vaccination among infants of unscreened mothers or those who didn’t receive all three recommended vaccine worsened all negative outcomes.

“Results of this economic evaluation quantified the potential impact of changing ACIP recommendations,” the authors concluded. “Even brief delays in HepB vaccine initiation were associated with a substantial increase in HBV infections, adverse health outcomes, and health care costs.”

In a Cornell University news release, senior author Noele Nelson, MD, PhD, MPH, said the study likely underestimated the costs and health outcomes linked to delays in administering the HBV vaccine birth dose. “Our model assumptions were conservative,” she said. “For example, we didn’t include the increasing risk of getting HBV infection from members of their household or community, which could happen if the number of people with HBV infection increases.”

The latest ACIP recommendations were at least partly based on low HBV infection rates, but Nelson said that the low incidence in the United States is, in fact, a direct result of successful HBV vaccination programs.

“Multiple studies have shown that the later children receive their first hepatitis B vaccination, the lower the probability they will complete their routine vaccination course,” she said, adding that the vaccines are safe and likely confer lifetime protection against HBV. “This policy may reverse this progress towards hepatitis B elimination.”

Real-world implementation drives impact

In an editorial on both studies, Grace Lee, MD, MPH, of Stanford University, said that the new, more-complex CDC recommendations have created unprecedented implementation challenges for providers. “As health systems and health care professionals are keenly aware, implementation is not about intent, it is about friction,” she wrote. “With enough friction, it becomes easier to not vaccinate than to vaccinate.”