A key federal vaccine advisory panel, whose members were recently replaced by Health Secretary Robert F. Kennedy Jr., is considering delaying administration of the hepatitis B vaccine until age 4. It is currently given to newborns.
Delaying the hepatitis vaccine — specifically the hepatitis B vaccine, which is the only hepatitis vaccine recommended for newborns — can have serious and well-documented health consequences for both the individual child and the broader community.
Delay will dramatically increase the risk of chronic hepatitis B infection. Infants are at the highest risk of developing chronic hepatitis B if infected early in life. If a newborn contracts hepatitis B (most commonly from an infected mother during childbirth), the risk of developing chronic infection is as high as 80-90%. In contrast, adults who contract hepatitis B have less than a 5% risk of chronic infection. Delaying the birth dose of the vaccine increases the window of vulnerability. The longer the delay, the greater the risk that the infant will be exposed and become a chronic carrier.
Delay will cause higher rates of perinatal transmission. Mother-to-child transmission (also known as perinatal transmission) is highly efficient. Without timely vaccination, the risk of a newborn acquiring hepatitis B from an infected mother can be up to 90%. Clinical studies show a clear relationship between vaccination timing and infection rates. Vaccination within 24 hours of birth: 5.6% of infants of HBsAg-positive mothers became infected. Vaccination 24-47 hours after birth: 7% infected. Vaccination 48-96 hours after birth: 16.7% infected. Delaying the vaccine even by a day or two significantly increases the risk of infection.
President Donald Trump claimed on Monday that there is no need for early vaccination against hepatitis B because it is sexually transmitted. However, the most common way it spreads is from mother to child during birth. This is further complicated by the fact that most people, including pregnant women, don’t realize when they are infected.
Delay will increase the risk of severe long-term health outcomes. Chronic hepatitis B infection acquired in infancy can lead to cirrhosis (scarring of the liver), liver failure, hepatocellular carcinoma (liver cancer) and premature death. Most deaths from hepatitis B-related liver disease and cancer are due to infections acquired in infancy or early childhood — infections that could have been prevented by timely vaccination.
Delay will cause a lower completion rate of the full vaccine series. Delayed administration of the first dose is associated with incomplete vaccination. Only 45% of infants who missed the birth dose completed the full vaccine series by age 2, compared to 65% of those who received the birth dose on time. Delayed hepatitis B vaccination is also associated with lower uptake of other routine childhood vaccines, thereby compounding the risk of other preventable diseases.
There will be an increase in community transmission and a public health impact. Unvaccinated or delayed-vaccination infants are more likely to become chronic carriers, serving as reservoirs for ongoing transmission within families and communities. Countries with high coverage of timely hepatitis B vaccination have reduced the prevalence of chronic infection in children from 8-12% to less than 1-2%. In contrast, populations with delayed or incomplete vaccination see continued transmission and higher disease burden.
All major health organizations recommend the first dose of the hepatitis B vaccine be given within 24 hours of birth to prevent perinatal and early childhood transmission and its severe consequences. Delaying the vaccine is not recommended except in rare, specific clinical circumstances. Any delay increases the risk of infection and its sequelae.
Delaying the hepatitis B vaccine in newborns significantly increases the risk of chronic infection, severe liver disease, liver cancer and death. The risk is exceptionally high for infants born to hepatitis B-infected mothers. Still, all infants are at risk due to the possibility of undiagnosed maternal infection or early horizontal transmission. Timely vaccination — ideally within 24 hours of birth — is the only proven way to prevent these outcomes and is strongly recommended by all central health authorities.