Timely Birth Dose Vaccine to Prevent Vertical Transmission of Hepatitis B: A Single Center Experience on the Road to the WHO Elimination Goals in Italy

Vaccines (Basel). 2021 Jul 19;9(7):801. doi: 10.3390/vaccines9070801.

Abstract

Italy was one of the first industrialized countries to implement a program of routine vaccination against hepatitis B virus (HBV) infection. However, currently, no HBV vaccine is administered at birth if the screened mother is HBsAg negative, whilst babies born to HBsAg positive mothers are given vaccine and hepatitis B immunoglobulin, within 12-24 post-delivery hours. A single center retrospective analysis of policies and practices to prevent mother-to-child transmission of HBV was carried out, to evaluate their adherence to HBV care guidelines. Paired maternal-infant medical records for consecutive live births, between January 2015 and December 2019, were reviewed at the AOU Città della Salute e Scienza di Torino, where a total of 235/35,506 babies (0.7%) were born to HBsAg positive mothers. Markers of active viral replication, i.e., HBV DNA level and/or HBeAg, were reported in only 66/235 (28%) of the mothers' medical records. All newborns had immunoprophylaxis at birth: 61% at <12 h, 31% between 12 and 24 h, 7% between 24 and 36 h and 1% at >36 h. In 2019, two cases of vertical HBV transmission occurred, despite timely immunoprophylaxis, as their mothers' viral load was detected too late for antiviral prophylaxis. Missed early identification of pregnant women with high viremia levels or late vaccinations may contribute to perinatal HBV infection. Immunoprophylaxis should be given to babies born to HBsAg positive mothers at the latest within 12 h. In Italy, policies aimed at achieving the WHO 2030 goal of eliminating viral hepatitis should be further implemented.

Keywords: hepatitis B virus; immunoprophylaxis; prevention strategies; timely vaccination; vertical transmission.