Prevalence of hepatitis B virus infection among pregnant women and cord blood hepatitis B surface antigen positive newborns in sub-Saharan Africa and South Asia

Background: Newborns infected with Hepatitis B Virus (HBV) are at risk of chronic liver disease and hepatocellular carcinoma. Objectives: This study investigated the prevalence of HBV infection among pregnant women and cord blood Hepatitis B surface antigen (HBsAg) positivity of their newborns in Bangladesh, Bhutan, India, Ethiopia, Mozambique, Kenya, Nigeria, Mali, and South Africa. Study design: Randomly selected paired maternal and cord blood samples (n = 101 each site) taken at delivery were tested for HBsAg and Hepatitis B extractable antigen (HBeAg) in the women using a chemiluminescent microparticle immunoassay. Similarly, cord blood sample of newborn was assessed for HBsAg reactivity. HBV DNA was quantified using the Xpert® HBV viral load assay, followed by genotyping. Results: The overall prevalence of maternal HBsAg positivity was 5.5 % (95 %CI: 0.4 %–7.1 %; n = 50/909). HBsAg positivity was higher in African countries (7.3 %; 95 %CI: 5.4 %–9.6 %; n = 44/606) compared to South Asian countries (2.0 %; 95 %CI: 0.8 %–4.3 %; n = 6/303; p = 0.002). Relative to South Africa, there were higher odds of HBsAg sero-positivity in women from Mozambique ((aOR): 7.7, 95 %CI: 1.6 %–37.8 %) and Mali (aOR: 5.7; 95 %CI: 1.1 %–29.7 %). The rate of HBsAg positivity in cord blood of babies born to HBsAg positive women was 28.0 % (95 %CI: 17.1 %–42.3 %; n = 14/50), including 31.8 % (95 %CI: 19.5–47.4 %; n = 14/44) in African countries. No cord blood HBsAg positivity was observed in South Asia. Genotypic analysis revealed HBV genotypes A (41.7 %) and E (58.3 %) were pre-dominant. Conclusion: The high rate of cord blood positivity (28.0 %) for HBsAg underscores the urgency of enhancing HBV prevention strategies to meet the World Health Organization's target of a 90 % reduction in new HBV infections by 2030.