Hepatitis C virus genotype homogeneity and lack of major Sofosbuvir resistance-associated substitutions among blood donors in Ethiopia

Hepatitis C virus (HCV) is a hepatotropic virus that causes a spectrum of liver diseases. HCV genetic diversity influences transmission, pathogenesis, prognosis, and response to antiviral therapy. Moreover, resistance associated substitutions (RASs) challenged the existing antiviral treatment. However, data regarding circulating genotypes and RASs are limited in Ethiopia. Therefore, this study aimed to determine HCV genotypes and RASs among apparently healthy blood donors. This study used 97 archived anti-HCV-positive serum samples obtained from apparently healthy blood donors, collected in accordance with national routine blood collection practices. The partial HCV NS5B gene of 45 samples was amplified and sequenced using amplicon-based next-generation sequencing. Genotypes and subgenotypes were determined using NCBI BLAST, Geno2Pheno [hcv], and the Los Alamos HCV database, and a phylogenetic tree as a confirmation. The RASs were determined using Geno2Pheno [hcv]. Of the 97 anti-HCV- positive samples, 45 had detectable HCV RNA, of which 35 yielded high-quality sequences. These strains (n = 35) showed marked homogeneity in NS5B gene sequences: 34 were HCV genotype 4, all subgenotype 4d, and one was HCV genotype 2, subgenotype 2c. Most strains carried D310N, an RAS associated with ribavirin, while no RASs associated with sofosbuvir resistance were detected. There is HCV genotype homogeneity with HCV genotype 4, particularly HCV subgenotype 4d, predominating. No major sofosbuvir RASs were found, but ribavirin RAS D310N was common. Future studies should use broader geographic sampling and whole-genome sequencing to comprehensively characterize RASs, their distributions, clinical significance, and temporal trends, thereby guiding treatment strategies in Ethiopia.