Assessment of Hepatitis C Virus Diversity in Addition to the Frequency of Genotypes in Samples Analyzed Between 2009 and 2014 at the Reference Laboratory of National Health Institute Dr. Ricardo Jorge

Abstract

Introduction: The identification of genotypes was essential for the prognosis and treatment of hepatitis C virus chronic patients in recent years. The aims of the study were to know the frequency of genotypes diagnosed in the last six years at the laboratory, and reveal the contribution of an in-house assay for molecular characterization of viruses.
Material and Methods: The genotyping of hepatitis C virus by LiPA was performed in 923 samples, mostly from male individuals. The subtyping of hepatitis C virus by an in-house assay to target regions in the Core/E1 and/or NS5B was performed in 112 samples.
Results: We observed a high prevalence of genotype 1 (56.6%), with a frequency of subtype 1a four times higher compared to 1b. All cases of genotype 3 (27.5%) were subtype 3a. For the cases of genotype 4 (12.9%), it were identified subtypes 4a (65.5%), 4d (31%), 4b (1.7%) and 4c (1.7%). Recombinants intragenotype 2, the RF1_2k/1b, and mixed infections, were also identified.
Discussion: The most prevalent subtypes (1a and 3a) obtained are usually described in injecting drug users. Although most of the samples analysed match to inmates (78.4%), we cannot exclude any possible risk behaviors associated with illicit drug use.
Conclusions: The high prevalence of subtype 1a, the frequency and diversity of genotype 4, and the identification of recombined virus suggest modification of the molecular pattern of hepatitis C virus infection described in the past. The in-house assay proved to be useful for the correct classification of hepatitis C virus and improving knowledge about the diversity of virus circulating in the country.