TY - JOUR
T1 - Phylogenetic characterization of Central/Southern European lineage 2 West Nile virus
T2 - analysis of human outbreaks in Italy and Greece, 2013-2014
AU - Barzon, L.
AU - Papa, A.
AU - Lavezzo, E.
AU - Franchin, E.
AU - Pacenti, M.
AU - Sinigaglia, A.
AU - Masi, G.
AU - Trevisan, M.
AU - Squarzon, L.
AU - Toppo, S.
AU - Papadopoulou, E.
AU - Nowotny, N.
AU - Ulbert, S.
AU - Piralla, A.
AU - Rovida, F.
AU - Baldanti, F.
AU - Percivalle, E.
AU - Palù, G.
PY - 2015/12/1
Y1 - 2015/12/1
N2 - In recent years, West Nile virus (WNV) lineage 2 has been spreading and causing disease outbreaks in humans and animals in Europe. In order to characterize viral diversity, we performed full-length genome sequencing of WNV lineage 2 from human samples collected during outbreaks in Italy and Greece in 2013 and 2014. Phylogenetic analysis showed that these WNV lineage 2 genomes belonged to a monophyletic clade derived from a single introduction into Europe of the prototype Hungarian strain. Correlation of phylogenetic data with geospatial information showed geographical clustering of WNV genome sequences both in Italy and in Greece, indicating that the virus had evolved and diverged during its dispersal in Europe, leading to the emergence of novel genotypes, as it adapted to local ecological niches. These genotypes carried divergent conserved amino acid substitutions, which might have been relevant for viral adaptation, as suggested by selection pressure analysis and in silico and experimental modelling of sequence changes. In conclusion, the results of this study provide further information on WNV lineage 2 transmission dynamics in Europe, and emphasize the need for WNV surveillance activities to monitor viral evolution and diversity.
AB - In recent years, West Nile virus (WNV) lineage 2 has been spreading and causing disease outbreaks in humans and animals in Europe. In order to characterize viral diversity, we performed full-length genome sequencing of WNV lineage 2 from human samples collected during outbreaks in Italy and Greece in 2013 and 2014. Phylogenetic analysis showed that these WNV lineage 2 genomes belonged to a monophyletic clade derived from a single introduction into Europe of the prototype Hungarian strain. Correlation of phylogenetic data with geospatial information showed geographical clustering of WNV genome sequences both in Italy and in Greece, indicating that the virus had evolved and diverged during its dispersal in Europe, leading to the emergence of novel genotypes, as it adapted to local ecological niches. These genotypes carried divergent conserved amino acid substitutions, which might have been relevant for viral adaptation, as suggested by selection pressure analysis and in silico and experimental modelling of sequence changes. In conclusion, the results of this study provide further information on WNV lineage 2 transmission dynamics in Europe, and emphasize the need for WNV surveillance activities to monitor viral evolution and diversity.
KW - Europe
KW - genetic evolution
KW - genome sequencing
KW - Greece
KW - Italy
KW - molecular epidemiology
KW - phylogenetic analysis
KW - West Nile virus
KW - WNV lineage 1
KW - WNV lineage 2
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UR - http://www.scopus.com/inward/citedby.url?scp=84989159474&partnerID=8YFLogxK
U2 - 10.1016/j.cmi.2015.07.018
DO - 10.1016/j.cmi.2015.07.018
M3 - Article
C2 - 26235197
AN - SCOPUS:84940093812
VL - 21
JO - Clinical Microbiology and Infection
JF - Clinical Microbiology and Infection
SN - 1198-743X
IS - 12
ER -