Hepatitis E virus (HEV) infection in Bulgaria is endemic, as demonstrated by the seroprevalence of antibody against the virus in the general population and by the high prevalence of clinical cases registered. In this study, a deep Bayesian phylogenetic analysis has been performed to provide information on the genetic diversity and the spread of HEV genotypes in Bulgaria. Three different dataset of HEV virus were built for genotyping by the maximum likelihood method, for evolutionary rate estimate by Bayesian Markov Chain Monte Carlo (MCMC) approach, for demographic history investigation and for selective pressure analysis. The evolutionary rate for genotype 3e, was 3,51 x10-3 substitution/site/year (95% HPD: 1,45 x10-3 - 5,75 x10-3 ). The root of the tMRCA of the Bayesian Maximum clade credibility (MCC) tree of HEV 3e genotype corresponded to 1965 (HPD 95% 1949 - 1994). The Bulgarian sequences mainly clustered in a main clade (clade A). The monophyletic clade included all Bulgarian genotype 3e sequences. The demographic history showed a slight growth from 1995 to 2000, followed by a sort of bottleneck in 2010s, a peak in 2011 and a new growth to 2015. Selection pressure analysis did not show sites under positive pressure but Sixty-four statistically significant sites under negative selection. Molecular epidemiological surveillance by Bayesian phylogeny of HEV virus can contributes to trace the way of human infection after contact with swine source directly or heating meat improving public health control. This article is protected by copyright. All rights reserved.
Human hepatitis E virus circulation in Bulgaria: deep Bayesian phylogenetic analysis for viral spread control in the country
Sagnelli, Caterina;Sagnelli, Evangelista;
2018
Abstract
Hepatitis E virus (HEV) infection in Bulgaria is endemic, as demonstrated by the seroprevalence of antibody against the virus in the general population and by the high prevalence of clinical cases registered. In this study, a deep Bayesian phylogenetic analysis has been performed to provide information on the genetic diversity and the spread of HEV genotypes in Bulgaria. Three different dataset of HEV virus were built for genotyping by the maximum likelihood method, for evolutionary rate estimate by Bayesian Markov Chain Monte Carlo (MCMC) approach, for demographic history investigation and for selective pressure analysis. The evolutionary rate for genotype 3e, was 3,51 x10-3 substitution/site/year (95% HPD: 1,45 x10-3 - 5,75 x10-3 ). The root of the tMRCA of the Bayesian Maximum clade credibility (MCC) tree of HEV 3e genotype corresponded to 1965 (HPD 95% 1949 - 1994). The Bulgarian sequences mainly clustered in a main clade (clade A). The monophyletic clade included all Bulgarian genotype 3e sequences. The demographic history showed a slight growth from 1995 to 2000, followed by a sort of bottleneck in 2010s, a peak in 2011 and a new growth to 2015. Selection pressure analysis did not show sites under positive pressure but Sixty-four statistically significant sites under negative selection. Molecular epidemiological surveillance by Bayesian phylogeny of HEV virus can contributes to trace the way of human infection after contact with swine source directly or heating meat improving public health control. This article is protected by copyright. All rights reserved.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
