Abstract
BACKGROUND: Superinfection with the hepatitis D virus (HDV) leads to a more aggressive form of chronic hepatitis B. While around 5% of hepatitis B surface antigen (HBsAg)-positive individuals are estimated to be hepatitis B virus (HBV)-HDV dually infected globally, the time point of superinfection is unknown and repeated HDV testing is not yet supported by international guidelines. Inci-D is a post hoc analysis from 2 prospective cohorts to evaluate the HDV superinfection rate. METHOD: The Inci-D cohort consists of 2 HBV cohorts of clinical meta-data and stored plasma samples or dried-blood spots (DBS) from The Gambia (Prolifica) and France. RESULTS: Overall, samples from 1016 HBsAg-positive individuals were analyzed (625 from The Gambia, 391 from France); the baseline HDV prevalence was 1.1% (7/625) and 2.5% (10/391), respectively. The median age (interquartile range) was 38 (32-50) years, and 63% were male. Patients in the French cohort were older (P < .001), with higher liver enzymes (P < .001), were more often hepatitis B e antigen positive (P < .001) or anti-HCV positive (P < .001), and had more advanced liver disease (P < .001). In the Gambian cohort, after a median follow-up time of 5.98 years, 14 individuals were detected to be newly HDV antibody (Ab) positive (3.85/1000 patient-years). In the French cohort, after a median follow-up time of 2.1 years, 3 individuals were newly detected to be HDV Ab positive (3.70/1000 patient-years). CONCLUSIONS: Hepatitis Delta superinfection increases considerably in HBsAg-positive carriers in The Gambia as well as in France. These findings support consideration of repeated HDV serology testing in HBsAg-positive individuals.