A new multi-centre study has confirmed that newborns in India may not need the vaccination for Hepatitis-B infection. The study done in north India shows that many newborns are protected at birth by natural antibodies to Hepatitis-B virus and hence vaccination is not needed at birth.
Hepatitis-B virus (HBV) can cause chronic hepatitis, liver cirrhosis and lead to hepato-cellular carcinoma (HCC) in susceptible persons.
The study was launched by the ICMR to look at hepatitis-B infection rates in children vaccinated at birth compared to those vaccinated starting at six weeks. The findings of the study have been published in the Indian Journal of Pediatrics, and lend support to the government's pragmatic approach to vaccinate babies born at home starting at six weeks, instead of at birth.
India started vaccinating children against Hepatitis-B in 2011. It is given at birth to babies born in hospitals. However, since many babies are delivered at home, outside of healthcare settings, the government introduced the pragmatic programme schedule of HBV vaccination, wherein the vaccine is given starting at six weeks to children born outside such healthcare settings.
"We found that the birth dose was not needed as infection rates were the same regardless of birth dose," says Jacob Puliyel, the study's primary author and a pediatrician at St. Stephens Hospital in Delhi. Most babies are naturally immune to Hepatitis-B infection due to passive transfer of antibodies from the mother, he said.
The study involved 2,671 children from centres in Delhi, Rajasthan, Uttar Pradesh, Uttarakhand, and Gujarat. Of these, 880 children were fully immunised starting at birth and 686 were fully immunised but without the birth dose.
The study found that infection rate was similar even in those babies not given the birth dose, thereby supporting the government's programme.
The researchers also found high protective antibodies in children before vaccination, indicating that missing the birth dose does not cause much problem. "These natural antibodies may also be the reason why the hepatocellular cancer (HCC) rate in India is very low," says Puliyel, also a member of the government's technical advisory board on immunisation.
The findings of this study support that of another large ICMR study conducted in Andhra Pradesh in South India,in 2014, which also reported the presence of Hepatitis-B antibodies in children before vaccination.
The fact that a good number of non-vaccinated babies had high levels of antibodies suggest it could be protecting some babies early in life, at a time when they are vulnerable to develop chronic hepatitis.
However, mothers in highly immunised communities have lower Hepatitis-B antibody levels as the vaccine induces lower antibody levels than natural infection. The antibody levels of vaccinated cohorts are then no longer boosted by exposure to wild-type infection. Babies born to these mothers will correspondingly have lower levels of antibodies, says Puliyel. "Therefore, paradoxically, nation-wide Hepatitis-B vaccination may reduce natural antibody transfer to newborns and there is a possibility it may increase incidence of HCC instead of reducing it."
Puliyel, however, cautions that more studies are needed to confirm this before changes in immunisation practice can be recommended.
