Ending the Universal Hepatitis B Birth Dose Would Raise Chronic Infections by 19 to 83 Percent, a New Model Projects
An Annals of Internal Medicine model of one U.S. birth cohort, published Oct. 20, projects 19 percent more chronic infections by age 20 if the first dose waits until 2 months and 83 percent more under shared decision-making. The federal change it models is on hold in court.
Ending universal hepatitis B vaccination at birth would raise chronic infections by age 20 by about 19 percent with the first dose at 2 months, and about 83 percent under shared decision-making, an Annals of Internal Medicine model projects.
The paper, Projected Effect of 2026 Federal Changes to the Childhood Immunization Schedule on Chronic Hepatitis B Virus Infections in the United States, was published online Oct. 20. Its authors are at Mass General Brigham, which announced the findings, and Medical Xpress reported them on Oct. 19. These are projections, not observed infections.
What did the model find?
It projected 255 chronic infections by age 20 in one birth cohort with universal birth dosing, 303 with the first dose deferred to 2 months and 467 under shared decision-making, according to the Mass General Brigham release. The 19 and 83 percent figures are relative increases over universal birth dosing.
The investigators used a Markov cohort model of one U.S. birth year, about 3.6 million infants, followed for 20 years and validated against Centers for Disease Control and Prevention estimates of pediatric infections. The shared decision-making scenario assumed half of infants were vaccinated at 2 months or later. Infants of mothers known to be hepatitis B-positive were vaccinated in every scenario. The model also projected that about 232,000 people would remain susceptible at age 20 under universal birth dosing, versus about 474,000 with deferral and about 1.8 million with shared decision-making.
“Even a small increase in childhood HBV infections could have large clinical, public health, and economic effects,” said corresponding author Amir Mohareb, MD, an infectious disease physician at Mass General Brigham, in the release. He added that policymakers “should re-implement recommendations for universal hepatitis B vaccination at birth.”
The absolute numbers are small for a cohort of 3.6 million. The model's point is that the gap grows with every family that defers and every mother whose screening result is missing.
What is the policy status of the birth dose?
The change the model tests is on hold. On Dec. 5, 2025, the Advisory Committee on Immunization Practices (ACIP), the CDC's vaccine advisory panel, voted 8 to 3 to drop the universal birth dose for infants of mothers who test negative for hepatitis B surface antigen, and the CDC adopted individual-based decision-making for that group, suggesting a first dose no earlier than 2 months when the birth dose is skipped. A January 2026 CDC memo then revised the childhood schedule.
On March 16, a federal judge in Massachusetts stayed the votes of the reconstituted committee and the January memo in a suit brought by the American Academy of Pediatrics and other groups, Georgetown's Center for Children and Families explained. The government's appeal of the part blocking committee appointees was argued Oct. 6, and the ACIP's October meeting was canceled. The CDC's posted schedule notes, dated July 2025, still call for one dose within 24 hours of birth for medically stable infants of at least 2,000 grams born to HBsAg-negative mothers, and a dose within 12 hours when the mother is positive or her status is unknown.
How does it compare with earlier modeling?
A JAMA Pediatrics model published April 27 pointed the same way for neonatal infections. With 86 percent maternal screening, universal vaccination yielded a median of 1,292 neonatal infections, and a targeted approach added 69 at 80 percent birth-dose coverage among infants of unscreened mothers, or 628 at 10 percent coverage.
Both models depend on assumptions about maternal screening and parental uptake. The Mass General Brigham release does not report cirrhosis, liver cancer or death outcomes.
What it means in clinic
For now, the posted CDC schedule still lists the birth dose for every newborn, and hospital order sets can follow it. The practical checks are local: confirm a hepatitis B surface antigen result is in the chart before delivery, treat an unknown status as a reason to give the dose within 12 hours, and document the discussion when a family declines. For the court fight behind the schedule, see our report on the canceled October ACIP meeting.
Reported, fact-checked and edited by The Script Pad's editorial staff.
This article is for professional education and does not replace clinical judgment. Treatment decisions should be based on the individual patient and current guidelines.
