{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,26]],"date-time":"2026-09-26T12:00:30Z","timestamp":1790424030075,"version":"4.1.0"},"reference-count":34,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2020,4,18]],"date-time":"2020-04-18T00:00:00Z","timestamp":1587168000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100009878","name":"Regione del Veneto","doi-asserted-by":"publisher","award":["Reference Centres"],"award-info":[{"award-number":["Reference Centres"]}],"id":[{"id":"10.13039\/501100009878","id-type":"DOI","asserted-by":"publisher"}]},{"name":"H2020 grant agreement 874735 - VEO project","award":["874735"],"award-info":[{"award-number":["874735"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Viruses"],"abstract":"<jats:p>West Nile virus (WNV) lineage 2 is expanding and causing large outbreaks in Europe. In this study, we analyzed the epidemiological, clinical, and virological features of WNV lineage 2 infection during the large outbreak that occurred in northern Italy in 2018. The study population included 86 patients with neuroinvasive disease (WNND), 307 with fever (WNF), and 34 blood donors. Phylogenetic analysis of WNV full genome sequences from patients\u2019 samples showed that the virus belonged to the widespread central\/southern European clade of WNV lineage 2 and was circulating in the area at least since 2014. The incidence of WNND and WNF progressively increased with age and was higher in males than in females. Among WNND patients, the case fatality rate was 22%. About 70% of blood donors reported symptoms during follow-up. Within the first week after symptom onset, WNV RNA was detectable in the blood or urine of 80% of patients, while 20% and 40% of WNND and WNF patients, respectively, were WNV IgM-seronegative. In CSF samples of WNND patients, WNV RNA was typically detectable when WNV IgM antibodies were absent. Blunted or no WNV IgM response and high WNV IgG levels were observed in seven patients with previous flavivirus immunity.<\/jats:p>","DOI":"10.3390\/v12040458","type":"journal-article","created":{"date-parts":[[2020,4,21]],"date-time":"2020-04-21T04:49:38Z","timestamp":1587444578000},"page":"458","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":41,"title":["Human West Nile Virus Lineage 2 Infection: Epidemiological, Clinical, and Virological Findings"],"prefix":"10.3390","volume":"12","author":[{"given":"Monia","family":"Pacenti","sequence":"first","affiliation":[{"name":"Microbiology and Virology Unit, Padova University Hospital, I-35128 Padova, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Alessandro","family":"Sinigaglia","sequence":"additional","affiliation":[{"name":"Department of Molecular Medicine, University of Padova, I-35121 Padova, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Elisa","family":"Franchin","sequence":"additional","affiliation":[{"name":"Microbiology and Virology Unit, Padova University Hospital, I-35128 Padova, Italy"},{"name":"Department of Molecular Medicine, University of Padova, I-35121 Padova, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Silvana","family":"Pagni","sequence":"additional","affiliation":[{"name":"Microbiology and Virology Unit, Padova University Hospital, I-35128 Padova, Italy"},{"name":"Department of Molecular Medicine, University of Padova, I-35121 Padova, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3902-8356","authenticated-orcid":false,"given":"Enrico","family":"Lavezzo","sequence":"additional","affiliation":[{"name":"Department of Molecular Medicine, University of Padova, I-35121 Padova, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Fabrizio","family":"Montarsi","sequence":"additional","affiliation":[{"name":"Istituto Zooprofilattico Sperimentale delle Venezie, I-35020 Legnaro PD, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Gioia","family":"Capelli","sequence":"additional","affiliation":[{"name":"Istituto Zooprofilattico Sperimentale delle Venezie, I-35020 Legnaro PD, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0720-8456","authenticated-orcid":false,"given":"Luisa","family":"Barzon","sequence":"additional","affiliation":[{"name":"Microbiology and Virology Unit, Padova University Hospital, I-35128 Padova, Italy"},{"name":"Department of Molecular Medicine, University of Padova, I-35121 Padova, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2020,4,18]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"38","DOI":"10.1016\/j.jcv.2018.08.007","article-title":"Ongoing and emerging arbovirus threats in Europe","volume":"107","author":"Barzon","year":"2018","journal-title":"J. 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