Diversity, geographical distribution and predictive factors of Hepatitis C virus genotypes and subtypes in Rwanda

Background

Existing data on the prevalence of hepatitis C virus (HCV) genotypes and subtypes in Rwanda need to be strengthened. The aim of this study was to identify HCV genotypes and subtypes among HCV-infected patients, as well as their geographical distribution in Rwanda, and to identify the social and economic factors that could influence HCV epidemiology which would make it possible to target national preventive and management actions for infected patients.

Methods

This study included 560 patients with confirmed chronic HCV infection. Patients were recruited from various health facilities in the four provinces of Rwanda as well as in the City of Kigali and had never received treatment with direct-acting antiviral (DAAs). HCV viral loads were measured using Cobas® AmpliPrep/Cobas® TaqMan® HCV Quantitative Test, version 2.0. HCV genotyping was performed using an in-house sequencing protocol targeting the NS5B central region. Genotypic HCV prevalence was correlated with patient geographic location, sociodemographic, behavioral, lifestyle, and clinical factors.

Results

HCV genotype 4 was detected in 99.3% of the patients, while genotype 3 was identified in 0.7%. A total of eight (8) HCV subtypes were detected, with 4k being the predominant subtype nationwide (49.5%), followed by subtypes 4r (21.2%), 4q (16.2%), 4v (7.9%), 4b (2.0%), 4l (1.8%), 4c and 3h represent 0.7% each. Our findings reveal subtype distribution variations among provinces. Subtype 4k was prevalent across regions, particularly in Kigali (64.0%) and the Eastern Province (61.6%). Subtype 4q was more common in the northern province (40.7%), 4r in the southern (43.9%) and western provinces (37.1%), and 4v in the eastern province (17.8%). Farmers exhibit a distinct infection profile compared to other occupations, showing a lower prevalence of subtype 4k but a higher prevalence of subtype 4r.

Conclusions

Our study revealed that HCV infection is unevenly distributed in Rwanda, dominated by HCV genotype 4, with considerable heterogeneity in the repartition of the different subtypes. We found potential associations between rural/urban lifestyles and HCV subtype profiles. Determined HCV distribution and diversity can serve as basis not only for HCV infection awareness and prevention campaigns, but also success and guidance for personalized treatment.