Hepatitis B in Africa Collaborative Network: cohort profile and analysis of baseline data

Journal article

Hepatitis B virus (HBV) remains endemic in the WHO Africa region, despite an effective vaccine. Evidence from Africa suggests transmission at household- and community-levels (“horizontal”) is an important driver of HBV transmission, in addition to perinatal transmission. To reach the WHO goal of HBV elimination by 2030, additional prevention approaches are needed for HBV control in Africa, but require a better understanding of local HBV epidemiology. In this dissertation, I describe HBV in households through two cross-sectional studies in the Democratic Republic of Congo (DRC). In the first study, we introduced point-of-care (POC) HBsAg screening within the existing HIV antenatal care (ANC) program in DRC’s capital city, Kinshasa, and we evaluated HBsAg-positivity among pregnant women and their household members. We found HBsAg-positivity prevalence was 5.0% (95% CI: 1.9%-8.0%) in households of women who were positive in ANC compared with 1.9% (0.0%-3.9%) in households of women who were negative in ANC. We observed associations between HBsAg positivity and older age, street barber use, shared nail clippers, and sexual behaviors.We then conducted a deeper investigation of HBV in selected households, evaluating medical histories, HBV serology, and HBV whole-genome sequencing using recently developed methods. Serological analysis showed that only 43% of reportedly HBV-vaccinated children had protective immunity. Analysis of consensus HBV sequences identified HBV genotypes A, D, and E and evidence of horizontal HBV transmission in one household cluster.In the second household study, we used survey and biospecimens from a nationally representative study to evaluate HBsAg-positivity in 5,679 children aged 6-59 months. We observed a national HBsAg-positivity prevalence of 1.3% (95% CI: 0.9%-1.7%) with substantial regional variation of 0% to 6% across 26 large provinces. Lack of tetanus antibodies (proxy for HBV vaccination), male sex, rural locale, lower household wealth, living outside the capital city’s province, and living with an HBV-infected adult were statistically significantly associated with higher HBsAg-positivity in children.Together, these studies highlight opportunities for contextualized HBV prevention, including tailored vaccine distribution, protection during sexual contact, and sanitation of shared personal items. We identify future scientific directions, including vaccine efficacy and immunogenicity and sexual dimorphism in childhood HBV infection.Doctor of Philosoph

Authors: Riches, N; Vinikoor, M; Guingane, A; Johannessen, A; Lemoine, M

• Publication status: Published
• Peer review status: Peer reviewed
• Publisher: Cambridge University Press
• Journal: Epidemiology & Infection
• Volume: 151
• Pages: e65-e65
• Article number: e65
• Publication date: 2023-04-03
• DOI: 10.1017/s095026882300050x
• EISSN: 1469-4409
• ISSN: 0950-2688
• Language: English
• Keywords: Virus; Natural history; Virology; Hepatitis B virus; Internal medicine; Hepatitis B; Medicine; Cohort study; Baseline (sea); Interquartile range; HBsAg; Family medicine; Asymptomatic; Demography; Biology; Environmental health; Population; HBeAg; Cohort