Risks of Delaying Newborn Hepatitis B Vaccination: Increased Infections and Deaths

Two new studies published in JAMA Pediatrics project that a recent change in U.S. Vaccination policy regarding the hepatitis B birth dose could lead to a significant increase in neonatal infections, chronic liver disease, and premature deaths among children.

The research addresses a policy shift by the Centers for Disease Control and Prevention (CDC), which adopted a recommendation from the Advisory Committee on Immunization Practices (ACIP) in December 2025. The new guidance moves away from a decades-old universal birth-dose recommendation, instead suggesting individual-based decision-making for infants born to mothers who test negative for the hepatitis B virus.

Projected Impact on Public Health

Under the current CDC guidance, infants born to mothers who test positive for hepatitis B or whose status is unknown should still receive the vaccine within 12 hours of birth. However, for infants born to mothers who test negative, the ACIP recommends that parents decide whether to vaccinate later, suggesting the first dose not be administered before two months of age.

One study, conducted by researchers from Oregon Health and Science University, Emory University, Cornell University, and the Los Angeles County Department of Public Health, used mathematical modeling to estimate the consequences of this delay. The researchers estimated that delaying the first dose to two months of age for infants of mothers who tested negative could result in:

• An additional 90 infections annually.
• 76 additional chronic infections per year.
• 29 additional hepatitis B-related deaths annually.
• More than $16 million in additional health care costs for each year’s birth cohort.

A second study, involving researchers from Boston University, Johns Hopkins University, and the University of Florida, found that avoiding an increase in neonatal infections under this targeted recommendation would require historically unattained levels of maternal [hepatitis B] screening or birth-dose coverage among infants of unscreened mothers.

This study estimated that the number of additional annual infections could range from 69, if 80% of the infants recommended for a birth dose received one, up to 628, if only 10% of those infants were vaccinated.

Medical Risks of Delayed Vaccination

Hepatitis B is a highly infectious virus transmitted through bodily fluids. While the virus can often be cleared by the immune systems of adults, the risk is significantly higher for infants. According to the research, babies who become infected have a 90% chance of developing a chronic hepatitis B infection.

The long-term consequences of chronic infection in childhood are severe. approximately a quarter of those who develop the chronic condition will die prematurely from liver disease triggered by the infection.

Policy Controversy and Legal Challenges

The shift in recommendation has drawn criticism from public health experts and medical organizations. Arthur Reingold, a professor of infectious disease epidemiology at the UC Berkeley School of Public Health and a former ACIP member, described the JAMA Pediatrics studies as very thoughtful analyses and suggested that previous versions of the ACIP would have reviewed such data before altering birth-dose recommendations.

The policy change has also led to legal and regional friction. In mid-March 2026, a federal court judge, Brian E. Murphy, issued a preliminary ruling in a case brought by the American Academy of Pediatrics (AAP) and other organizations. Judge Murphy ruled that the restructuring of the ACIP and the subsequent changes to vaccination policy were likely illegal.

several states have announced they will not adopt the new CDC recommendation, leaving the actual implementation of the policy uncertain across different jurisdictions.