Phylogenetic Analysis of NS5B Region of Hepatitis C Genotype 3a Virus among Different Risk Groups in Iran

Background: Hepatitis C virus (HCV) is a major cause of liver diseases. Transmission of HCV, as a blood-borne virus, is a major concern for the safety of blood products. In Iran, intravenous drug abuse is a major risk factor for HCV transmission. Recently a change in the distribution of HCV genotype among Iranian blood donors has been reported, and genotype 3a is reported as the most frequent genotype. Also, genotype 3a is the dominant genotype among IDUs. Objective: To investigate the association between HCV genotype 3a circulating in the community, sequences of HCV genotype 3a were analyzed among different risk groups in Iran. Methods: In this cross-sectional study, a partial sequence of the NS5B region of the HCV genome was isolated from 58 blood donors, 48 intravenous drug users (IDUs), and 31 patients with inherited bleeding disorders (IBDs) infected with HCV genotype 3a were included. The published sequence data were obtained from the Gen Bank database and were compared to construct the phylogenetic trees. Results: Of 58 blood donors infected with subtype 3a, 31 (53.5%) reported the risk of intravenous drug abuse. In the phylogenetic tree, no separate cluster was formed to differentiate between HCV sequences in blood donors and IDUs. A cluster at the middle level was found in the phylogenetic tree formed by sequences from blood donors, IDUs, and patients with inherited bleeding disorders. Conclusions: The phylogenetic tree showed the phylogenetic mixing of genotype 3a sequences in BDs, IBD patients, and IDUs. The results confirmed the extensive transmission of IDU-related genotype 3a towards the general population.

Look-Back Study of Transfusion-Transmitted Hepatitis C Virus Infection in Iran

Background: With the identification of blood donors with a subsequent positive result in HCV screening and the possibility of HCV transmission via their previous negative donations, the role of look-back investigation has been crucial in enhancing blood safety. A retrospective study was conducted to identify the fate of blood components from donors subsequently found to be confirmed HCV positive cases with previous negative donations. Objectives: This look-back study aimed to determine the transfusion-induced hepatitis C virus infection through previous HCV-negative donations of subsequent HCV positive blood donors in Iran. Methods: In this study, all serologically confirmed HCV positive blood donors across the country from December 2015 to June 2017 were included. A look-back process was conducted by tracing back previous HCV negative donations of subsequent HCV-positive blood donors to specific recipients, according to the IBTO instructions. The HCV RNA testing was carried out using an in-house one-step TaqMan real-time RT-PCR assay. Results: During the study period, 280 serologically confirmed HCV-positive blood donors were included, with 267 as first-time, nine as repeated, and three as regular donors. Of the participants, the first-time donors were excluded, the repeated donors were not eligible, and only the regular donors were selected for the look-back study. The HCV RNA was detected in one regular donor, but HCV infection was not detected in his previous donation recipient. In addition, more than two HCV risk factors were reported by each regular blood donor. Conclusions: According to the results, evidence of HCV transmission via previous blood transfusions and the risk of HCV infection was not observed among recipients. Due to the reporting of some HCV risk factors by the subjects, paying proper attention to the donor selection process is highly recommended.