Epidemiology and Sociodemographic Determinants of HBsAg Seropositivity with Complementary Liver Biomarker Analysis among Late-Adolescent and Adult Sub-Saharan African Migrants in Al-Kufra, Libya

Abstract

Background: Hepatitis B virus (HBV) remains a major cause of cirrhosis, hepatocellular carcinoma and liver failure, while migrants from endemic settings can face substantial barriers to diagnosis, vaccination and continuity of care. We estimated hepatitis B surface antigen (HBsAg) seroprevalence and sociodemographic determinants among newly arrived late-adolescent and adult sub-Saharan African migrants in Al-Kufra, southeastern Libya, and illustrate biochemical patterns across HBV-related liver-disease stages.

Methods: We analyzed cross-sectional participant-level data collected from June 2025 to February 2026. The primary sample comprised 539 migrants aged 18-63 years; ages 18-19 were considered late adolescence and no participant was younger than 18 years. HBsAg was measured using the mini VIDAS HBsAg Ultra assay. Prevalence was summarized using Wilson 95% confidence intervals, and associations were evaluated using chi-square tests and modified Poisson regression with robust standard errors to estimate adjusted prevalence ratios (aPRs); a secondary logistic model assessed discrimination and calibration. Several liver function tests were performed on hepatitis B patients, including transaminase (AST and ALT) and total bile acid (TBA) levels, among healthy individuals, patients with chronic hepatitis B (CHB), patients with liver cirrhosis (LC), patients with hepatocellular carcinoma (HCC), and patients with liver failure (LF). The two data sets were not combined at the participant level.

Results: In the primary migrant cohort, 148/539 participants were HBsAg positive (27.5%; 95% CI 23.9-31.4). Prevalence was 32.7% in participants aged 18-19 years and varied from 9.1% among Malian to 47.8% among Eritrean participants. In adjusted analysis, Eritrean nationality was associated with higher HBsAg prevalence than Sudanese nationality (aPR 1.81, 95% CI 1.09-3.00), whereas primary education (aPR 0.63, 95% CI 0.44-0.90) and secondary/higher education (aPR 0.20, 95% CI 0.10-0.41) were associated with lower prevalence. Each 10-year increase in age was associated with lower adjusted prevalence (aPR 0.82, 95% CI 0.69-0.97). The secondary model had AUC 0.737 (bootstrap 95% CI 0.693-0.781) with no evidence of poor calibration (Hosmer-Lemeshow p=0.745). The biochemical results of liver function tests related to hepatitis B in the participants migrating from Al-Kufra showed that the mean concentration of thiobarbituric acid (TBA) increased from 3.99 µmol/L in healthy individuals to 24.94 µmol/L in patients with chronic hepatitis B, 39.94 µmol/L in patients with cirrhosis, 45.79 µmol/L in patients with hepatocellular carcinoma, and 203.51 µmol/L in patients with liver failure. Patients with liver failure also showed the highest mean concentrations of aspartate aminotransferase (AST) (410.24 U/L) and alanine aminotransferase (ALT) (561.83 U/L).

Conclusions: HBsAg positivity was exceptionally high in this migrant sample, with marked heterogeneity by nationality and educational attainment. The findings support entry-point HBV testing linked to confirmatory assessment, vaccination of susceptible individuals and culturally responsive follow-up rather than risk-based exclusion from testing. We conclude that analyzing vital signs and biochemical tests performed on liver function in migrant participants via Kufra is important for assessing liver function associated with hepatitis B virus infection.