Evidence of West Nile virus lineage 2 circulation in Northern Italy

Istituto G. Caporale Teramo, Via Campo Boario, 64100 Teramo, Italy.
Veterinary Microbiology (Impact Factor: 2.51). 02/2012; 158(3-4):267-73. DOI: 10.1016/j.vetmic.2012.02.018
Source: PubMed


A West Nile virus (WNV) strain belonging to lineage 2 was for the first time detected in two pools of Culex pipiens collected in the province of Udine and in tissues of a wild collared dove (Streptopelia decaocto) found dead in the province of Treviso, in North East of Italy. It was molecularly identified by group and WNV lineage specific RT-PCRs and characterized by partial sequencing of the NS3 and NS5 genes. When compared with the sequences of same fragments of NS3 and NS5 of the WNV lineage 2 strain isolated from birds of prey in Hungary (2004), the phylogenetic analysis of these sequences revealed 100% and 99% similarity, respectively. As the Hungarian strain, the NS3 selected sequence differed from the 2010 Greek isolate by one amino-acid located at 249 site which is the site involved in genetic modulation of WNV pathogenicity. The Italian and Hungarian strains have histidine rather than proline at this site. The presence of a lineage 2 strain in regions where the lineage 1 strain is still circulating, creates a new scenario with unpredictable consequences. In this situation comprehensive investigations on the occurrence, ecology, and epidemiology of these different WNV strains circulating in Italy become the highest priority.

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    • "In Italy, WNV first appeared in 1998 in the Padule di Fucecchio mash area, in Tuscany, (Autorino et al. 2002); and then it was detected in the North-Eastern part of Italy in 2008 (Calistri et al. 2010b, Monaco et al. 2010) where it became endemic (Monaco et al. 2009). Unrelated new foci were also reported in Central and Southern Italy (Calistri et al. 2010a) and, more recently, lineage 2 strains were detected in Central (Bagnarelli et al. 2011) and Northern-eastern parts of Italy, as well as in Sardinia (Savini et al. 2012, Capelli et al. 2013). "

    Full-text · Dataset · Nov 2015
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    • "During 2011 in Italy the WNV caused several outbreaks among horses and birds. Lineage 2 strain was found in two pools of Culex pipiens collected in Friuli-Venezia Giulia region and in the tissues of a resident collared dove (Streptopelia decaocto) found dead in Veneto region, in northeast Italy [80]. During the summer of 2011, WNV lineage 2 was also detected in urine samples of a febrile patient in Marche region [81] and in a patient coming from northeastern Sardinia. "
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