Neonatal hepatitis B vaccination protects mature adults from occult virus infection

Area of Science:

• Hepatology and Virology
• Vaccinology and Immunology
• Public Health and Epidemiology

Background:

• Neonatal hepatitis B virus (HBV) vaccination is standard practice, yet the long-term protection against occult HBV infection (OBI) in adulthood requires definition.
• The serological status of HBsAg-negative and anti-HBc-positive [HBsAg(-)/anti-HBc(+)] is a marker for potential OBI, particularly in individuals vaccinated during infancy.

Purpose of the Study:

• To evaluate the long-term efficacy of neonatal HBV vaccination in preventing OBI in mature adulthood.
• To assess the prevalence of HBsAg(-)/anti-HBc(+) status and HBV DNA in adults who received infant HBV vaccination versus a control group.

Main Methods:

• A cohort study building upon the Qidong Hepatitis B Intervention Study (1983-1990) sampled 28-35-year-old participants in 2012.
• Serological markers (HBsAg, anti-HBs, HBeAg, anti-HBe, anti-HBc) were tested for all participants.
• HBV-DNA and relaxed circular DNA (rcDNA) were determined in HBsAg(-)/anti-HBc(+) individuals.

Main Results:

• The vaccination group showed significantly lower prevalence of HBsAg (1.58%) and HBsAg(-)/anti-HBc(+) (4.70%) compared to the control group (7.45% and 19.48%, respectively; p < 0.001).
• Prevalence of HBsAg(-)/anti-HBc(+) increased with age in the control group but was uncertain in the vaccination group.
• HBV-DNA was detected in 13.08% of HBsAg(-)/anti-HBc(+) individuals from the vaccination group and 4.18% from the control group; HBV rcDNA was found in most HBV-DNA positive samples.

Conclusions:

• Occult HBV infection (OBI) can occur in vaccinated adults, indicated by the presence of HBV DNA in HBsAg(-)/anti-HBc(+) individuals.
• Despite OBI occurrence, neonatal HBV vaccination provides effective long-term protection against OBI in mature adults, significantly reducing overall prevalence.