Impact of universal hepatitis B vaccination on antenatal hepatitis B prevalence in the Midlands region of the North Island, New Zealand.

ABSTRACT

AIM: Universal hepatitis B vaccination has now been in place in New Zealand for 22 years. A retrospective laboratory data study has been carried out to give objective evidence of the impact that this is having on hepatitis B prevalence in the antenatal population. METHOD: A retrospective data search was performed of all antenatal hepatitis B surface antigen (HepBsAg) tests carried out at Pathlab Laboratories between 1997 and 2009. RESULTS: When the change in prevalence with time is examined, there is a clear downwards trend in antenatal hepatitis B prevalence rates from 1997 to 2009. Dividing the antenatal population into different age groups, the downward trend is most marked for those aged =20 years. CONCLUSION: The prevalence of hepatitis B infection in the antenatal population in the Midlands region of New Zealand is now declining and is likely to be as a result of the introduction of the hepatitis B vaccine onto the universal schedule throughout New Zealand in 1988. This would also explain why the decrease is most marked in antenatal women below the age of 20.