{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,18]],"date-time":"2026-05-18T14:23:56Z","timestamp":1779114236635,"version":"3.51.4"},"reference-count":33,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2026,5,18]],"date-time":"2026-05-18T00:00:00Z","timestamp":1779062400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"European Union Horizon 2020 Research and Innovation Programme","award":["874735"],"award-info":[{"award-number":["874735"]}]},{"name":"Ministry of Health in Greece"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["TropicalMed"],"abstract":"<jats:p>Usutu virus (USUV) is a mosquito-borne flavivirus, widely distributed in Central Europe, where it causes avian outbreaks with large-scale mortality. Although most human infections are asymptomatic or mild, the reports of USUV neurologic infections are increasing, especially among immunocompromised patients. Cross-reactivity in serological and molecular assays is often seen between USUV and the genetically and antigenically related West Nile virus (WNV). Here, we report the first USUV infection in Greece in an asymptomatic blood donor who tested positive in the automated nucleic acid test during screening for WNV, which is endemic in the country. Following the blood donation surveillance plan, a serum sample taken two weeks post-donation was tested for WNV IgM and IgG antibodies. The borderline index of the IgM antibodies, combined with negative result for IgG antibodies, raised the suspicion of molecular cross-reactivity with USUV. Although the USUV-specific PCR in donor\u2019s plasma was negative, its result was positive following amplification of the virus in cell culture, as USUV RNA was detected in the culture supernatant confirming the USUV infection. Whole genome sequence was taken using an Ion Torrent next-generation sequencing platform. Phylogenetic analysis showed that the Greek strain clusters within the USUV Europe 2A genetic lineage. The detection of USUV human infection in Greece prompts for surveillance studies to elucidate its epidemiology and ecology in the country.<\/jats:p>","DOI":"10.3390\/tropicalmed11050138","type":"journal-article","created":{"date-parts":[[2026,5,18]],"date-time":"2026-05-18T12:36:40Z","timestamp":1779107800000},"page":"138","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["First Usutu Virus Infection in an Asymptomatic Blood Donor in Greece"],"prefix":"10.3390","volume":"11","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-6643-3322","authenticated-orcid":false,"given":"Anna","family":"Papa","sequence":"first","affiliation":[{"name":"Department of Microbiology, Medical School, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5200-8045","authenticated-orcid":false,"given":"Katerina","family":"Tsioka","sequence":"additional","affiliation":[{"name":"Department of Microbiology, Medical School, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2249-2443","authenticated-orcid":false,"given":"Styliani","family":"Pappa","sequence":"additional","affiliation":[{"name":"Department of Microbiology, Medical School, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0009-0009-0483-3724","authenticated-orcid":false,"given":"Danai","family":"Pervanidou","sequence":"additional","affiliation":[{"name":"National Public Health Organisation, 15123 Athens, Greece"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Constantina","family":"Politis","sequence":"additional","affiliation":[{"name":"National Public Health Organisation, 15123 Athens, Greece"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Kostas","family":"Stamoulis","sequence":"additional","affiliation":[{"name":"Hellenic National Blood Transfusion Center, 13672 Athens, Greece"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Vassiliki","family":"Bakaloudi","sequence":"additional","affiliation":[{"name":"Blood Center, AHEPA University General Hospital, 54636 Thessaloniki, Greece"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2026,5,18]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"e232","DOI":"10.1017\/S0950268819001213","article-title":"Usutu virus: A new threat?","volume":"147","author":"Cle","year":"2019","journal-title":"Epidemiol. 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