Molecular epidemiology of hepatitis C infection in Cyprus within the general population and high-risk cohorts

HCV Phylogeography of the General Population and High-Risk Groups in Cyprus Identifies the Island as a Global Sink for and Source of Infection

Hepatitis C virus (HCV) genotype and subtype distribution differs according to geographic origin and transmission risk category. Previous molecular epidemiology studies suggest the presence of multiple subtypes among Cypriot subjects. To investigate HCV genotype- and subtype-specific dissemination patterns, origins, and transmission in Cyprus, we analyzed HCV sequences encoding partial Core-E1 and NS5B regions. Analyzed populations comprised the general population and high-risk cohorts in Cyprus and a globally sampled dataset. Maximum-likelihood phylogeny reconstruction with bootstrap evaluation, character reconstruction using parsimony, and bootstrap trees estimated by ML were performed to identify the geographic origin of HCV subtypes and statistically significant dispersal pathways among geographic regions. Phylogeographic analyses traced the origin of subtypes in the general population and among PWID in Cyprus to unique and overlapping globally distributed regions. Phylogenetic analysis in Core-E1 revealed that most sequences from incarcerated populations in Cyprus clustered with the general population and PWID. We estimate that HCV infections in Cyprus originate from multiple global sources while most HCV transmissions among incarcerated individuals occur locally. This analysis is one of a few studies tracing HCV dispersal patterns using global datasets, and these practices and findings should inform how HCV epidemics are targeted by future prevention policies.

HCV dispersal patterns among intravenous drug users (IDUs) in Athens metropolitan area

BACKGROUND

Most of the HCV transmission the recent years in Greece was among IDUs. Our aim was to estimate the prevalence of HCV genotypes and to investigate the patterns of HCV dispersal among IDUs in Athens using current state of the art molecular epidemiology methods.

METHODS

HCV sequences were determined from 238 HIV-negative IDUs collected on the basis of the "ARISTOTLE" prevention program carried out in Athens between 2012 and 2013. Phylogenetic trees were inferred on HCV sequences isolated from IDUs in Athens for the most prevalent HCV clades (subtypes 1a and 3a). Phylogenetic analysis was performed by Neighbor-Joining and Bayesian methods using GTR+G as nucleotide substitution model. HCV dispersal patterns were estimated using as references, all globally available HCV sequences for subtypes 1a and 3a.

RESULTS

The prevalence of HCV subtypes was: 3a (59.2%), 1a (21.9%), 4 (13.0%), 1b (5.4%) and 2 (0.5%). Phylogenetic analyses revealed that most sequences (63.5%) οf subtypes 1a and 3a fell within IDU-specific monophyletic groups. The proportion of sequences in monophyletic clades was similar for subtype 3a (62.9%) and 1a (65.3%). For the latter group, monophyletic clades were smaller in size. Multivariable logistic regression analyses showed that monophyletic clustering was marginally associated recent onset of injecting ([AOR]=1.44; 95% CI (0.97-2.13), p=0.068).

CONCLUSIONS

The high proportions of HCV sequences within IDU-specific monophyletic clusters suggest that transmissions occurred locally among IDUs in Greece. The numerous clusters for both 1a and 3a provide evidence that both sub-epidemics were the result of multiple introductions among the IDUs. Higher regional clustering was probably associated with a more recent onset of drug use.

The Distribution of Hepatitis C Virus Genotypes in Middle Eastern Countries: A Systematic Review and Meta-Analysis

CONTEXT

The hepatitis C virus (HCV) is classified into seven genotypes and more than 100 subtypes. The treatment regimen, duration and efficacy of HCV therapy may vary according to the HCV genotype. Therefore, the HCV genotype should be determined prior to antiviral therapy. The objective of the current study was to review systematically all studies reporting the distribution of HCV genotypes in the countries that make up the Middle East.

EVIDENCE ACQUISITION

Articles were identified by searching electronic databases, including Scopus, PubMed and Google scholar, with timeline limits (articles published between 1995 and 2016). We carried out a systematic search regarding the distribution of HCV genotypes in Middle Eastern countries.

RESULTS

A total of 579 studies were identified by the electronic search. Of these, a total of 187 were identified as eligible papers including 60,319 patients who were meta-analyzed for pooled distribution of HCV genotypes. In Turkey, Israel, Cyprus, and Iran, genotype 1 was the most prevalent HCV genotype with rates of 82% (95% CI, 82%-83%), 68% (95% CI, 67%-69%), 68% (95% CI, 59%-77%), and 55% (95% CI, 54%-55%), respectively. In Egypt, Iraq, Saudi Arabia, and Syria, HCV genotype 4 was the most common genotype with rates of 86% (95% CI, 85%-88%), 60% (95% CI, 56%-64%), 56% (95% CI, 54%-55%), and 57% (95% CI, 54%-61%), respectively. On the basis of adjusted data, HCV genotype 4 was the most prevalent genotype in the Middle East region, with a rate of 74.7% (95% CI, 73.4%-76%), followed by genotype 1 at 15.1% (95% CI, 14.1%-16%).

CONCLUSIONS

Our results showed that HCV genotype 4 is the most prevalent genotype in the Middle East region. However, HCV genotype 1 is the most prevalent among non-Arab countries in the region including Turkey, Iran, Cyprus, and Israel.