Hepatitis B Virus Prevalence and Mother-to-Child Transmission Risk in an HIV Early Intervention Cohort in KwaZulu-Natal, South Africa

Jane Millar; Gabriela Z L Cromhout; Noxolo Mchunu; Nomonde Bengu; Thumbi Ndung'u; Philip J Goulder; Philippa C Matthews; Anna L McNaughton

doi:10.1093/ofid/ofad366

Hepatitis B Virus Prevalence and Mother-to-Child Transmission Risk in an HIV Early Intervention Cohort in KwaZulu-Natal, South Africa

Open Forum Infect Dis. 2023 Jul 15;10(8):ofad366. doi: 10.1093/ofid/ofad366. eCollection 2023 Aug.

Authors

Jane Millar¹, Gabriela Z L Cromhout^{2

3}, Noxolo Mchunu², Nomonde Bengu^{2

4}, Thumbi Ndung'u^{2

5

6}, Philip J Goulder¹, Philippa C Matthews^{6

7

8}, Anna L McNaughton⁹

Affiliations

¹ Department of Paediatrics, University of Oxford, Oxford, UK.
² HIV Pathogenesis Programme, The Doris Duke Medical Research Institute, University of KwaZulu Natal, Durban, South Africa.
³ Department of Paediatrics and Child Health, University of KwaZulu Natal, Durban, South Africa.
⁴ Department of Paediatrics, Queen Nandi Regional Hospital, Empangeni, South Africa.
⁵ Africa Health Research Institute, Durban, South Africa.
⁶ Division of Infection and Immunity, University College London, London, UK.
⁷ The Francis Crick Institute, London, UK.
⁸ Department of Infectious Diseases, University College London Hospital, London, UK.
⁹ Nuffield Department of Medicine, University of Oxford, Oxford, UK.

Abstract

Background: HIV and hepatitis B virus (HBV) prevalence are both high in KwaZulu-Natal, South Africa. HIV coinfection negatively affects HBV prognosis and can increase the likelihood of HBV mother-to-child transmission (MTCT). In an early HIV infant treatment intervention cohort of HIV-transmitting mother-child pairs in KwaZulu-Natal, we characterized maternal HBV prevalence and screened infants at risk.

Methods: Infants were treated for HIV MTCT at birth, and combination regimens incidentally active against HBV were initiated within 21 days. Maternal samples (N = 175) were screened at birth for HBV infection (HBV surface antigen [HBsAg]), exposure to HBV (HBV anti-core IgG), and vaccination responses (HBV anti-S positive without other HBV markers). Infants of mothers who were HBV positive were screened for HBsAg at 1 and 12 months.

Results: Evidence of HBV infection was present in 8.6% (n = 15) of maternal samples. Biomarkers for HBV exposure were present in 31.4% (n = 55). Evidence of HBV vaccination was uncommon in mothers (8.0%; n = 14). Despite prescription of antiretroviral therapy (ART) active against HBV, HBV DNA was detectable in 46.7% (7/15) of mothers who were HBsAg positive. Three mothers had HBV viral loads >5.3 log₁₀ IU/mL, making them high risk for HBV MTCT. Screening of available infant samples at 1 month (n = 14) revealed no cases of HBV MTCT. At 12 months, we identified 1 HBV infection (1/13), and serologic evidence of vaccination was present in 53.8% (7/13) of infants.

Discussion: This vulnerable cohort of HIV-transmitting mothers had a high prevalence of undiagnosed HBV. Early infant ART may have reduced the risk of MTCT in high-risk cases. Current HBV guidelines recommend ART prophylaxis, but these data underline the pressing need to increase availability of birth dose vaccines.

Keywords: HIV; PMTCT; South Africa; antiretroviral therapy; hepatitis B virus.

Associated data

figshare/10.6084/m9.figshare.22118381.v1

Abstract

Associated data

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