BACKGROUND AND AIMS: The prevalence of hepatitis delta virus (HDV) infection among persons living with hepatitis B virus (HBV) and its impact on liver-related complications in West Africa are ill-defined. Wetested a large urban HBV cohort in Senegal for the presence of HDV/HBV co-infection and evaluated its association with liver fibrosis. METHODS: We included persons with positive hepatitis B surface antigen (HBsAg) enrolled in the SEN-B cohort since 2019. Anti-HDV antibodies (HDVAb) were tested using the Anti-HD Diasorin LiaisonXL test, HDV RNA was measured with RT-qPCR and genotyping was determined through sequencing. We used multivariable logistic regression to evaluate the association between HDVAb positivity and liver fibrosis, defined as a liver stiffness measurement >
7.0 kPa. RESULTS: We analysed 914 individuals with a median age of 32 years (interquartile range [IQR] 26-41), of whom 487 (53.3%) were men and 117 (12.8%) had HIV co-infection. Thirteen participants (1.4%, 95% CI 0.8-2.4) had a positive HDVAb test, of whom 8/13 (61.5%) showed detectable HDV RNA. HDV genotype 5 was found in 75.0% of cases. In multivariable analyses, HDVAb positivity (aOR 11.7, 95% CI 3.1-45.7), male sex (aOR 5.4, 95% CI 3.1-10.3), ALT >
40 IU/L (aOR 4.4, 95% CI 2.4-8.2) and HBeAg positivity (aOR 4.6, 95% CI 1.8-11.9) were independently associated with liver fibrosis. CONCLUSION: The prevalence of HDV infection was low in persons living with HBV in Dakar, but those affected had a very high risk of presenting with liver cirrhosis. Efforts to improve HDV screening and management are urgently needed in Senegal.