Update on the HDV seroprevalence and genotype distribution among patients positive for HBsAg referred to a National Reference Laboratory in Cameroon between January 2019 and December 2020.

Objectives: Cameroon is known to be endemic for hepatitis B virus infection, but available data on hepatitis delta virus (HDV) prevalence and genetic diversity are limited, inconsistent, and outdated. This study aimed to assess the current HDV prevalence and determine the HDV genotype distribution among patients positive for hepatitis B surface antigen (HBsAg) in Cameroon. Methods: This cross-sectional study examined patients positive for HBsAg from Cameroon's 10 administrative regions. Anti-HDV antibodies and HDV viral load (VL) were tested using validated commercial enzyme-linked immunosorbent assay and HDV VL quantification assays. HDV genotypes were determined by the Sanger sequencing method, followed by phylogenetic analysis of the "HDV R0" genome region previously described. Results: Of the 859 patients positive for HBsAg tested, 142 (16.5%) tested positive for anti-HDV, and HDV RNA was detected in 110 (77.5%) of them. The southern region of Cameroon had the highest infection rate. Notably, an undetectable hepatitis B virus VL was significantly associated with HDV infection (P <0.001). Patients younger than 15 years were the least infected (10%). Five genotypes-HDV-1 (the more prevalent, 83.6%), HDV-5, HDV-6, HDV-7, and HDV-8-were found in the studied population. Conclusions: Cameroon remains an endemic country for HDV, exhibiting high prevalence, remarkable regional distribution, and wide genetic diversity.