Delaying hepatitis B vaccination at birth increases risk of infant infection

Delaying hepatitis B vaccination after birth increases the risk of infection in newborns and reduces their survival rates and quality of life, according to a new study from Cornell University.

The paper, “Economic Evaluation of Delaying the Infant Hepatitis B Vaccination Program,” is under embargo until April 27, 2026, at 11 a.m. EST. JAMA Pediatrics.

The study found that the longer the delay, the greater the cost to human life and health care, with costs ranging from $16 million to $370 million depending on the age of first vaccination and adherence to the vaccination schedule.

Chronic hepatitis B is a leading cause of cirrhosis, liver failure, liver cancer, and death, affecting 2.4 million people in the United States. Newborns are at greatest risk: 90% of newborns infected with hepatitis B virus (HBV) will develop long-term infection and 25% will die prematurely from cirrhosis or liver cancer.

“Preventing HBV transmission at birth is a cornerstone of hepatitis B elimination efforts,” said Noel Nelson, professor of practice in the Department of Public and Ecosystem Health, senior author of the study.

In December 2025, the federal Advisory Committee on Immunization Practices (ACIP) voted to delay the first dose of HBV vaccine for infants whose birth parents tested negative for the virus – a reversal of the 2018 recommendation to vaccinate all infants within 24 hours of birth.

In this study, Nelson and his team used probabilistic models based on published scientific data about hepatitis B vaccine efficacy, transmission rates, and disease progression to estimate the number of infections and health care costs that would occur under different vaccine scenarios.

Nelson compared models where vaccination was given at birth or delayed to 2 months, 7 months, 4 years, or 12 years of age in children of HBV-negative birth parents, unknown birth parent infection status, or both. Their models also consider cases where all children received all three recommended doses, or were incompletely vaccinated.

All estimates showed that, in the unvaccinated groups, more individuals progressed to chronic infections or serious complications such as cirrhosis and liver cancer. This effect was increased in scenarios where children do not receive all three doses as prescribed.

Importantly, our study underestimates the costs and health consequences associated with delaying birth doses of hepatitis B vaccine. Our model assumptions were conservative. For example, we did not take into account the increased risk of acquiring HBV infection from members of their household or community, which may occur if the number of people with HBV infection increases.”

Noel Nelson, Professor of Practice, Department of Public and Ecosystem Health

The latest ACIP recommendation was based, in part, on lower HBV infections. Nelson argues that the low incidence of HBV infection in the United States is a direct result of successful vaccination programs.

“Several studies have shown that the later children get their first hepatitis B vaccination, the less likely they are to complete their routine vaccination course,” Nelson said. “This policy could reverse this progress toward hepatitis B elimination.”

The recent ACIP decision also cited concerns about the safety of the hepatitis B vaccine and speculation that the harms may outweigh the benefits of vaccination. Reviewing four decades of studies, including recent comprehensive safety reviews, Nelson found no evidence of serious adverse reactions such as seizures, other neurological disorders, infections or mortality.

“We found that data over 35 years demonstrate long-term immunogenicity and potential lifetime protection from hepatitis B vaccines,” Nelson said. “We see no benefit in delaying the first dose of this vaccine, and our findings favor maintaining a policy of universal hepatitis B vaccination at birth.”

Additional authors include Eric W. Hall of Oregon Health & Science University; Prabhu Gounder of the Los Angeles County Department of Public Health; and Heather Bradley of Emory University.