title: Phylogeny of Murray Valley encephalitis virus in Australia and Papua New Guinea.
abstract: OBJECTIVE
  To study the genetic diversity of Murray Valley encephalitis virus (MVEV) in Australia and Papua New Guinea.
  
  
  METHODS
  MVEV envelope gene sequences were aligned using Clustal X and manual editing was performed with Bioedit. ModelTest v. 3.7 was used to select the simplest evolutionary model that adequately fitted the sequence data. Maximum likelihood analysis was performed using PhyML. The phylogenetic signal of the dataset was investigated by the likelihood mapping analysis. The Bayesian phylogenetic tree was built using BEAST.
  
  
  RESULTS
  The phylogenetic trees showed two main clades. The clade Ⅰ including eight strains isolated from West Australia. The clade Ⅱ was characterized by at least four epidemic entries, three of which localized in Northern West Australia and one in Papua New Guinea. The estimated mean evolutionary rate value of the MVEV envelope gene was 0.407 × 10(-3) substitution/site/year (95% HPD: 0.623 × 10(-4)-0.780 × 10(-3)). Population dynamics defines a relative constant population until the year 2000, when a reduction occurred, probably due to a bottleneck.
  
  
  CONCLUSIONS
  This study has been useful in supporting the probable connection between climate changes and viral evolution also by the vector point of view; multidisciplinary monitoring studies are important to prevent new viral epidemics inside and outside new endemic areas.
authors.affiliation: Department of Infectious, Parasitic and Immunomediated Diseases, National Institute of Health, Rome, Italy; Department of Public Health and Infectious Diseases, Sapienza University of Rome, Rome, Italy.
authors.forename: Eleonora
authors.initials: E
authors.lastname: Cella
authors.affiliation: University of Rome 'La Sapienza', Italy.
authors.forename: Ivan
authors.initials: I
authors.lastname: Gabrielli
authors.affiliation: L. Sacco Department of Biomedical and Clinical Sciences, University of Milan, Italy.
authors.forename: Gianguglielmo
authors.initials: G
authors.lastname: Zehender
authors.affiliation: Department of Infectious, Parasitic and Immunomediated Diseases, National Institute of Health, Rome, Italy; University of Rome 'Tor Vergata', Italy.
authors.forename: Marta
authors.initials: M
authors.lastname: Giovanetti
authors.affiliation: Department of Infectious, Parasitic and Immunomediated Diseases, National Institute of Health, Rome, Italy.
authors.forename: Alessandra Lo
authors.initials: AL
authors.lastname: Presti
authors.affiliation: L. Sacco Department of Biomedical and Clinical Sciences, University of Milan, Italy.
authors.forename: Alessia
authors.initials: A
authors.lastname: Lai
authors.affiliation: Clinical Pathology and Microbiology Laboratory, University Hospital Campus Bio-Medico of Rome, Italy.
authors.forename: Giordano
authors.initials: G
authors.lastname: Dicuonzo
authors.affiliation: Clinical Pathology and Microbiology Laboratory, University Hospital Campus Bio-Medico of Rome, Italy.
authors.forename: Silvia
authors.initials: S
authors.lastname: Angeletti
authors.affiliation: Department of Pathology and Laboratory Medicine, University of Florida, Gainesville, FL, USA.
authors.forename: Marco
authors.initials: M
authors.lastname: Salemi
authors.affiliation: Department of Infectious, Parasitic and Immunomediated Diseases, National Institute of Health, Rome, Italy; University Hospital Campus Bio-Medico, Rome, Italy. Electronic address: ciccozzi@iss.it.
authors.forename: Massimo
authors.initials: M
authors.lastname: Ciccozzi
keywords: Evolution; Murray valley encephalitis virus; Phylogeny