Vertical transmission of hepatitis C virus (HCV) remains a global concern
Trickey A et al, Lancet Gastroenterol Hepatol. 2025;10(10):904-914
A global modelling study estimates that around 74,000 children worldwide are infected with HCV each year through vertical transmission. Based on the well-founded assumption that two-thirds of these children will spontaneously clear the virus by the age of five, approximately 23,000 chronic HCV infections arise annually from mother-to-child transmission. Southern Asia and Africa are particularly affected. The study highlights the need to implement HCV screening and antiviral therapy during pregnancy.
Background: The burden of hepatitis C virus (HCV) among women of childbearing age remains high globally. Studies have estimated that 7–12% of children born to women with HCV infection will acquire HCV, although around two-thirds of children will then clear their HCV infection by 5 years of age. The authors aimed to estimate the annual number of vertically transmitted HCV infections and how many cases remain at 5 years of age at the country or territory, regional, and global levels.
Methods: In this data synthesis study, the authors produced estimates of vertical HCV transmission by combining data from several sources: data on the number of women, age-specific fertility rates, mortality rates among children aged 0-5 years, and HIV prevalence among women aged 15–49 years from the UN; modelled data on HCV prevalence among women aged 15–49 years; meta-analysis data on HCV-HIV co-infection prevalence; and recent estimates of the probabilities of vertical HCV transmission and subsequent clearance by age 5 years. The annual number of births with HCV was estimated by multiplying the number of women with HCV in 5-year age bands by age band-specific birth rates, separately by HIV status, and multiplying by HIV status-specific HCV vertical transmission probabilities. The number of births with HCV was multiplied by the probability of spontaneous clearance of HCV by 5 years of age, accounting for mortality. All estimates were sampled 1000 times from their uncertainty intervals (UIs) to produce 95% UIs.
Findings: The estimated annual global number of new HCV infections occurring through vertical transmission was 73,862 (95% UI: 69,808–78,279). Southern Asia (21,245 [18,095–24,847]), western Africa (16,482 [14,873–18,283]), and eastern Africa (8182 [7479–9085]) were the regions with the most infections. Pakistan (16,350 [13,325–19,844]) and Nigeria (8483 [6944–10,184]) had the largest burden and together accounted for around a third of new infections. The authors estimated that 23,120 (20,596–25,813) of these children would be alive and still have HCV when aged 5 years.
Interpretation: Targeted screening policies that test and treat pregnant women with HCV could prevent substantial numbers of new HCV infections; however, data on the safety of HCV treatments in pregnant women are required.