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.

Epidemiology of hepatitis C virus in Iran

In Iran, the prevalence of hepatitis C virus (HCV) infection is relatively low according to the population-based epidemiological studies. However, the epidemiology of HCV is changing and the rate of HCV infection is increasing due to the growth in the number of injecting drug users in the society. In addition, a shift has occurred in the distribution pattern of HCV genotypes among HCV-infected patients in Iran. Genotype 1a is the most prevalent genotype in Iran, but in recent years, an increase in the frequency of 3a and a decrease in 1a and 1b have been reported. These variations in the epidemiology of HCV reflect differences in the routes of transmission, status of public health, lifestyles, and risk factors in different groups and geographic regions of Iran. Health policy makers should consider these differences to establish better strategies for control and prevention of HCV infection. Therefore, this review was conducted to present a clear view regarding the current epidemiology of HCV infection in Iran.

Prevalence of hepatitis C virus genotypes in Iranian patients: a systematic review and meta-analysis

CONTEXT

Hepatitis C virus (HCV) is a global public health problem and a major etiology of chronic liver disease, which may develop into cirrhosis and hepatocellular carcinoma. Genotypes of HCV indicate the route of acquisition, the clinical outcome, response to treatment, prognosis and control strategies.

OBJECTIVES

The aim of this study was to estimate the overall prevalence and trend of HCV genotypes or subtypes in Iran.

DATA SOURCES

A literature review was done for papers reporting HCV genotypes in Iranian patients in PubMed, Magiran, IranMedex, Scientific Information Databank, and Google scholar databases.

STUDY SELECTION

Data were selected according to inclusion and exclusion criteria.

DATA EXTRACTION

Data were abstracted by two independent authors. Data were analyzed based on random-effects model using the Meta R. Pooled statistical software. Prevalence of HCV genotypes in cities and provinces of Iran with 95% confidence interval (CI) were calculated.

RESULTS

Fifty-three articles published between 1999 and 31 June 2014 including 22952 HCV infected individuals were included in the meta-analysis. Subtype 1a was predominant with a rate of 39% (95% CI: 34-44%); followed by subtype 3a, 32% (95% CI: 26-39%); subtype 1b, 13% (95% CI: 10-15%); genotype 4, 5.18% (95% CI: 3.27-7.5%); and genotype 2, 3.6% (95% CI: 1.6-8.3%). Untypeable HCV had a rate of 0.11% (95% CI: 0.07-0.16%).

CONCLUSIONS

The most frequent subtypes of HCV in Iran were 1a, 3a and 1b, respectively. This frequency differed in various provinces of Iran and fluctuated with time. It is important to determine the distribution of HCV genotypes in different geographical areas and its trend with time for epidemiological and patients' management purposes.