Reduced prevalence of hepatitis B surface antigen positivity among pregnant women born after the national implementation of immunoprophylaxis for babies born to hepatitis B virus‐carrier mothers in Japan

摘要

Aim We aimed to estimate hepatitis B surface antigen (HBsAg) positivity among birth year‐stratified pregnant women in Hiroshima, Japan, and compare prevalence rates between women born before and after implementation of a national immunoprophylactic vaccination program for babies born to hepatitis B virus (HBV) carrier mothers in Japan. Methods Pregnant women who gave birth at all delivery hospitals/clinics in Hiroshima prefecture between 1 April 2010 and 31 March 2011 were eligible. Lists collected from each institution included survey items such as age (pregnant woman's birth year) and HBsAg and hepatitis C virus (HCV) antibody (anti‐HCV) test results, which were posted anonymously and non‐consolidated from medical records. We calculated the HBsAg and anti‐HCV prevalence in our cohort according to the mothers' birth year. Results In 41 of 58 hospitals/clinics, 15?233 and 15?035 pregnant women underwent HBsAg and anti‐HCV testing, corresponding to 59.6% and 58.9% of 25?546 births in the 2010 fiscal year, respectively. The overall HBsAg positive rate was 0.51% (95% confidence interval [CI], 0.40–0.63%), and an extremely low prevalence (0.10%; 95% CI, 0.00–0.25%) was observed among pregnant women born after 1986. However, the prevalence in this study was slightly higher than the nationwide value (0.31%) and the Chugoku region‐specific value (0.46%) among first‐time blood donors at Japanese Red Cross blood centers between 2001 and 2006. No significant difference in anti‐HCV positivity was observed. Conclusion Only two pregnant women born after the preventive program implementation were HBsAg‐positive. Perinatal HBV transmission is estimated to be almost completely inhibited in the next generation.