Vic preterm babies support hep B vaccine for all newborns

Existing recommendations to immunise all newborns against hepatitis B within 24 hours of birth are supported by a new study involving 818 preterm babies in Victoria — the largest of its kind in the world. Led by Melbourne’s Murdoch Children’s Research Institute (MCRI), the study found that babies born before 29 weeks gestation who had a hepatitis B virus (HBV) vaccine shortly after birth were not more likely than unvaccinated babies to be diagnosed with bronchopulmonary dysplasia (BPD).

BPD is a severe lung disease that is common among very preterm babies and can cause a range of developmental and health challenges including asthma, heart problems and neurodevelopmental disability. The Vaccine Safety Health Link (VSHL) was used for this study, which joins together multiple statewide immunisation and health outcome datasets. It found that 51% of the vaccinated babies went on to develop BPD, compared to 62% in the unvaccinated group.

As the most common blood-borne virus in Australia, HBV attacks the liver and can be passed on in utero. Babies that are infected are 90% more likely to develop chronic infection compared with those infected later in infancy or childhood. The most effective preventive intervention for HBV is vaccination, with World Health Organization and Australian guidelines recommending that all children receive a birth dose HBV vaccine, no matter their size.

And yet, the rates of vaccination for HBV among preterm babies vary across Australia and globally. According to MCRI, initial concerns were raised by Australian researchers, who observed an association between specific antibodies after vaccination and a higher risk of BPD developing. Given the recommendation to vaccinate, MCRI researcher and lead author of the published results of this study Hannah Morgan said it was a national priority to investigate this further, especially in Victoria, which had the data to draw on.

“This study identified no evidence of an increased risk of BPD in preterm infants who received the HBV vaccine compared to those who didn’t,” Morgan said. “Victoria is unique in that we can link anonymous, statewide data on vaccination with birth records, perinatal and the outcomes of babies, ensuring the latest safety information can be provided.” Established by the Centre for Health Analytics, the VSHL “has proven to be a powerful tool that continues to help us answer ongoing questions in vaccine research”, Morgan said.

Morgan said these findings support existing recommendations to immunise all newborns against hepatitis B within 24 hours of birth. It is also believed that they could help streamline decision-making in neonatal care units across the country. Together with SAEFVIC (the Surveillance of Adverse Events Following Vaccination in the Community), the datasets provide public health recommendations to inform the Victorian Immunisation Program.

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‘Birth-dose hepatitis B vaccination and bronchopulmonary dysplasia, Australia’, an online first version of this research, has been published in Bulletin of the World Health Organization. When available, you will be able to read the version of record at doi.org/10.2471/BLT.24.291683. Also contributing to the study’s findings were researchers from the University of Melbourne, Monash University, The Royal Children’s Hospital, Monash Children’s Hospital, La Trobe University and Hudson Institute of Medical Research.

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