title: Hepatitis C virus genotype 4d in Southern Italy: reconstruction of its origin and spread by a phylodynamic analysis.
abstract: Hepatitis C Virus (HCV) genotype 4 predominates in Middle East and Central Africa countries. Recently, it has become also prevalent in Southern European countries where it is thought to have been introduced through immigration and the movement of intravenous drug users. In Italy, the prevalence of genotype 4 is particularly high (4.5%) in Southern regions, such as Calabria, and reaches values of 8.4% in specific areas where there appears to be endemic circulation of this genotype. In the present study, the phylogeny of HCV subtype 4d isolated from 19 Italian patients in Calabria was investigated by analysing a fragment of the NS5B viral genomic region. A Bayesian coalescent-based framework was used to estimate origin and spread of the HCV 4d in this area. The mean evolutionary rate HCV 4d NS5B sequences was estimated using a dataset of sequences sampled at known times and a relaxed clock constant model that best fitted the data. By using a Bayesian coalescent method, the Italian 4d isolates collected in Calabria were found to share a common ancestor with reference 4d isolates whose origin was traced back to 1940s. The genotype 4d epidemic in Southern Italy was maintained in a steady non-expanding phase until the late 1970s after that it grew exponentially up to 1990s probably sustained by the vast increase of unsafe blood transfusions and the spread of illicit intravenous drug users.
authors.affiliation: Department of Infectious, Parasitic and Immunomediated Diseases, National Institute of Health, Rome, Italy. ciccozzi@iss.it
authors.forename: Massimo
authors.initials: M
authors.lastname: Ciccozzi
authors.forename: Michele
authors.initials: M
authors.lastname: Equestre
authors.forename: Angela
authors.initials: A
authors.lastname: Costantino
authors.forename: Nadia
authors.initials: N
authors.lastname: Marascio
authors.forename: Angela
authors.initials: A
authors.lastname: Quirino
authors.forename: Alessandra
authors.initials: A
authors.lastname: Lo Presti
authors.forename: Eleonora
authors.initials: E
authors.lastname: Cella
authors.forename: Roberto
authors.initials: R
authors.lastname: Bruni
authors.forename: Maria Carla
authors.initials: MC
authors.lastname: Liberto
authors.forename: Alfredo
authors.initials: A
authors.lastname: Focà
authors.forename: Giulio
authors.initials: G
authors.lastname: Pisani
authors.forename: Gianguglielmo
authors.initials: G
authors.lastname: Zehender
authors.forename: Anna Rita
authors.initials: AR
authors.lastname: Ciccaglione
mesh_terms: D019143:Evolution, Molecular; D005838:Genotype; D016174:Hepacivirus / Q000145:classification* / Q000235:genetics* / Q000302:isolation & purification; D006526:Hepatitis C / Q000453:epidemiology* / Q000821:virology*; D006801:Humans; D007558:Italy / Q000453:epidemiology; D017720:Molecular Epidemiology; D008969:Molecular Sequence Data; D058974:Phylogeography; D017422:Sequence Analysis, DNA; D017361:Viral Nonstructural Proteins / Q000235:genetics; D012324:RNA-Dependent RNA Polymerase
chemical_list: D017361:Viral Nonstructural Proteins; C087036:NS-5 protein, hepatitis C virus; D012324:RNA-Dependent RNA Polymerase