The Hepatitis B Shot America Calls Essential on Day One: Ontario Gives It in Grade 7

In 1991 the government’s immunization advisers admitted in writing something few American parents have ever read. For most of a decade the country had tried to stop hepatitis B by vaccinating the adults most likely to catch it: health workers, people who inject drugs, the sexual partners of carriers. In its 1991 recommendations, the committee conceded that this strategy “has not lowered the incidence of hepatitis B,” mostly because reaching high-risk adults before they were infected had not proved feasible. An estimated 200,000 to 300,000 Americans were being newly infected each year, and more than a third of acute patients had no readily identifiable risk factor. So the advisers turned to the one population the health system could reliably reach. Every infant would be vaccinated, with the first dose given “preferably before the infant is discharged from the hospital, but no later than when the infant is 2 months of age.”

Birth or two months: the country has spent the past ten months fighting over those two halves of that sentence, in committee rooms and in federal court. The universal infant dose was as much a logistics decision as a medical one. Babies became the delivery system for a program aimed at adults the system kept missing, and over time the “preferably” hardened into a deadline. A presentation at the December 2025 meeting of the CDC’s advisers dated the current 12-to-24-hour window to 2005. Ontario, Canada’s most populous province, chose differently, and its routine program still waits until grade 7.

The baby the birth dose was built for

The biology behind the birth dose is sound, and nobody in this fight disputes it. When a mother carries the virus, her baby is exposed during delivery, and the 1991 document put the risk of perinatal infection at 10 to 85 percent depending on the mother’s e-antigen status. An infant infected that way has a 90 percent risk of chronic infection, which brings cirrhosis and liver cancer decades later. For that baby, vaccine in the first hours of life paired with immune globulin is the whole game. Canada agrees. Its national immunization guide says every pregnant woman should be tested and that every infant born to an infected mother should get vaccine within 12 hours, with immune globulin as soon as possible.

The calculation changes when the mother’s test comes back negative, because the main route into a newborn, the mother’s blood at delivery, is largely closed. Largely, not entirely. A test can miss, a mother can be infected after her screen, a result can go astray between the lab and the delivery room, and the virus can still reach a child from an infected member of the household. That leftover risk is the best argument for a universal day-one shot. Look closely, though, and it says more about how reliably the American system screens and reports than about any individual baby.

Ten months of whiplash

On December 5, 2025, the reconstituted Advisory Committee on Immunization Practices voted 8-3 to drop the universal birth dose. For infants of mothers who tested negative, parents and clinicians would decide, and families who skipped the birth dose were advised to wait at least two months. Infants whose mothers were positive or untested kept the existing protocol, immune globulin included. On December 16, acting CDC director Jim O’Neill signed off, saying the change “reflects ACIP’s rigorous review of the available evidence.”

It didn’t hold. The American Academy of Pediatrics and allied medical groups sued, and on March 16, 2026, U.S. District Judge Brian E. Murphy in Boston issued a preliminary injunction. It stayed the January 5 schedule revision that had cut routinely recommended childhood immunizations from 17 to 11, the appointments of 13 committee members, and the votes of the reconstituted panel, which the plaintiffs say includes the December hepatitis B vote. The committee hasn’t met since, and this week’s scheduled session is listed on the CDC’s own meetings page as cancelled “due to ongoing litigation.” A newborn whose mother tested negative is back under the universal recommendation. What put the baby there was a professional association of the doctors who give the shot and a judge’s procedural ruling, not new evidence about that baby’s risk.

Grade 7, on purpose

TrialSite News put it bluntly this week: America’s hepatitis B debate “has a Canadian problem.” Ontario funds a voluntary school program in which public health nurses give grade 7 students two shots at least four to six months apart, and the province states its reasoning plainly: “The goal of the program is to vaccinate students against the hepatitis B virus while their risk of getting the virus is low.” An American pediatric society would read low risk as a reason to hurry. Ontario reads it as a reason to wait.

Ontario isn’t an outlier in Canada. According to a 2023 national review by CATIE, only New Brunswick, the Northwest Territories and Nunavut offered a birth dose. Alberta, British Columbia, Prince Edward Island, Quebec and Yukon started at two months, the same timing the December vote allowed and its critics called reckless, and the remaining five provinces vaccinated adolescents between nine and 12. The national guide recommends routine immunization for all children, but it says that “the age at which HB-containing vaccine is offered varies from jurisdiction to jurisdiction.” The firm rules apply where the risk actually is: screen every pregnancy, protect the exposed newborn within hours, and when a mother’s status is unknown, consider vaccinating while results are pending.

This is close to the structure the December vote tried to adopt, and Canada’s results are on file. In 2021 the Public Health Agency of Canada counted four reported acute hepatitis B cases in children under 15 nationwide, a rate of 0.07 per 100,000, and an all-ages acute rate of 0.30. The United States, with a universal birth dose in place the whole time, reported 2,214 acute cases in 2023, a rate of 0.7 per 100,000, and the CDC estimates the true number of infections at about 14,400.

These figures come with caveats, and they should be stated. The years differ, the drug epidemics differ, and acute surveillance misses silent infections, which is why the same Canadian report also logged 19 chronic or unspecified cases in children under 15. The agency itself warns that pandemic disruption probably held down its 2021 counts. None of this isolates what a birth dose does. It does show where the burden of proof belongs. If a day-one shot for babies of screened-negative mothers were what kept childhood hepatitis B down, a country where five provinces wait until adolescence ought to show a visible pediatric problem, and its reported numbers don’t. Cynthia Nevison, a CDC contractor, made a similar point about American history in her presentation to the committee. U.S. rates began falling in the 1980s with safe-sex promotion, needle exchange and the screening and case management of infected mothers, and she judged that the universal birth dose probably contributed very little to the decline in acute cases.

Who the screening gap covers

At the December meeting, the FDA’s Tracy Beth Hoeg asked why the United States vaccinates every newborn when Denmark does not. CDC staffer Adam Langer answered that Denmark is a country of 6 million people and that more than 95 percent of its pregnant women are screened for hepatitis B. Figures presented to the committee put American prenatal screening at 84 to 87 percent, down from 96.5 percent in the early 2000s.

The defenders’ strongest argument therefore concedes that roughly one in seven American mothers now reaches delivery without being tested, a failure of prenatal care that the birth dose has been covering since 1991. It also has little to do with the December change, because the vote explicitly kept the birth dose for every infant whose mother’s status was unknown. The babies in the screening gap were never at issue. The vote covered babies whose mothers had been tested and cleared, the group that Canada and Denmark have trusted their screening programs to protect for years.

The advocates’ own arithmetic

Canada came up at the meeting as the better comparison. The best-known Canadian analysis on the question is a 2023 CMAJ Open modeling study by Mia Biondi, Jordan Feld and colleagues, which urged Ontario to adopt birth-dose immunization. The Viral Hepatitis Care Network funded it, and its authors disclose consulting fees, honoraria or advisory roles with Gilead, AbbVie, Janssen, Roche, GSK, Merck and VBI Vaccines, three of which have sold hepatitis B vaccines. That doesn’t make the math wrong, but readers should know who did it.

The math itself makes a narrower case than its authors did. Measured against Ontario’s grade 7 program, the only option that saved money was a combined vaccine at two, four and six months. Every schedule that began at birth cost money per disability-adjusted life year averted, ranging from $103,000 Canadian for a single birth dose followed by combined shots to $1,675,000 for three separate doses starting at birth. The authors judged the cheapest of those cost-effective and recommended the birth dose anyway.

Then there are the infections. Between 2020 and 2050, the model has every birth-dose schedule preventing 560 acute pediatric infections relative to the grade 7 program, and the two-month combined schedule preventing 550. For chronic infections, the paper’s table gives 160 against 150, while its own summary rounds both to 160. Over thirty years in Canada’s largest province, then, starting at birth rather than at two months buys about 10 infections, by the advocates’ rounded figures. Nearly all of the benefit comes from vaccinating in infancy. The first 24 hours add very little.

Ontario’s own reformers seem to have read the paper the same way. On February 25, 2026, the Algoma Board of Health passed a motion asking the province’s Ministry of Health to fund a combined DTaP-HB-IPV-Hib vaccine at 2, 4 and 6 months of age, replacing the grade 7 dose. It does not mention a birth dose.

The December meeting also heard a safety argument that the defenders of the status quo never answered. CDC staffer Mark Blaxill told the committee that there were no randomized placebo-controlled trials of the vaccine in infants, that the trials usually cited followed children for seven days or less, and that “safety evidence is limited and often concerning.” Committee member Retsef Levi said that with such small numbers, short follow-up and no placebo comparisons, asking whether there is evidence of harm might be the wrong question. Cody Meissner, defending the universal dose, asked it anyway: “The question is, is there any evidence of harm? There is clearly evidence of benefit.” Kirk Milhoan answered more plainly: “It’s not risk-free.” Meissner’s question puts the burden on parents to show a harm that week-long, placebo-free trials could never have detected. When a product goes to most American newborns within hours of birth, that burden belongs on the product.

What happens next is up to three judges of the First Circuit in Boston, who heard the government’s appeal on October 6 and haven’t ruled. The academy’s attorney came away seeing a path for the court to keep Murphy’s order in place. If the panel frees the stayed appointees, the committee can meet again, and the December recommendation’s fate will turn on how much of the injunction survives. If the stay holds, the universal newborn dose stays in force by court order while the committee that would reexamine it remains unable to meet. North of the border, Ontario’s Ministry of Health has the Algoma motion on its desk, and even the reformers there are asking for two months, not day one.

Sources

1. CDC MMWR – Hepatitis B Virus: A Comprehensive Strategy for Eliminating Transmission in the United States Through Universal Childhood Vaccination (1991)
2. CMAJ Open – Biondi et al., cost-effectiveness modelling of birth and infant dose hepatitis B vaccination in Ontario (2023)
3. Public Health Agency of Canada – Hepatitis B in Canada: 2021 surveillance data update
4. CDC – 2023 Viral Hepatitis National Profile
5. Canadian Immunization Guide – Hepatitis B vaccines
6. Medical Economics – ACIP December 2025 hepatitis B presentations and deliberations
7. CIDRAP – CDC advisers drop decades-old universal hepatitis B birth dose recommendation (2025)
8. Contagion Live – CDC adopts individual-based decision-making for the hepatitis B birth dose (2025)
9. Medical Daily – AAP v. Kennedy: injunction, stayed votes and the First Circuit appeal (2026)
10. CDC – ACIP meeting information (October 2026 meeting cancelled)
11. InsideHealthPolicy – AAP attorney sees path for First Circuit to preserve lower court ACIP ruling (2026)
12. Windsor-Essex County Health Unit – Hepatitis B Immunization Program for Grade 7 Students
13. CATIE – What needs to happen to eliminate hepatitis B in Canada (2023)
14. Algoma Public Health – Motion 2026-19 on combined infant DTaP-HB-IPV-Hib vaccine (2026)
15. TrialSite News – America’s Hepatitis B Vaccine Debate Has a Canadian Problem: Ontario Waits Until Age 12 (2026)