{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,30]],"date-time":"2026-09-30T22:18:42Z","timestamp":1790806722641,"version":"4.1.0"},"reference-count":17,"publisher":"Wiley","issue":"8","license":[{"start":{"date-parts":[[2025,6,28]],"date-time":"2025-06-28T00:00:00Z","timestamp":1751068800000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by-nc-nd\/4.0\/"}],"content-domain":{"domain":["onlinelibrary.wiley.com"],"crossmark-restriction":true},"short-container-title":["Transfusion"],"published-print":{"date-parts":[[2025,8]]},"abstract":"<jats:title>Abstract<\/jats:title><jats:sec><jats:title>Background<\/jats:title><jats:p>We sought to examine the prevalence of West Nile Virus (WNV) nucleic acid test (NAT) positivity over time in Canadian blood donors, examine the level of false\u2010positive NAT screening, and understand the effectiveness of travel\u2010related testing outside of WNV seasonality in Canada.<\/jats:p><\/jats:sec><jats:sec><jats:title>Study Design and Methods<\/jats:title><jats:p>All blood donations in Canada (except Qu\u00e9bec) between 2018 and 2023 were tested by the Roche Cobas WNV\u2010NAT assay during the summer\u2013fall season by Canadian Blood Services. Testing for recent travel outside Canada was performed in the winter\u2013spring season. All 2023 WNV\u2010NAT\u2010positives were confirmed by two independent WNV\u2010specific polymerase chain reaction (PCRs).<\/jats:p><\/jats:sec><jats:sec><jats:title>Results<\/jats:title><jats:p>While WNV positivity varied by location and time, no increasing trend of positivity was observed over the 6\u2010year study period. No WNV\u2010NAT\u2010positive donors with a history of recent travel outside of Canada in the winter\u2013spring season were identified by donor screening (2018\u20132023). In total, 2,454,102 samples were tested during summer months and 267,988 in winter months. In 2023, WNV\u2010specific PCR confirmed 10 of 13 (76.9%) screening WNV\u2010NATs. Recent Japanese Encephalitis Virus (JEV) vaccination was identified as a potential false positive for initial WNV screening results.<\/jats:p><\/jats:sec><jats:sec><jats:title>Discussion<\/jats:title><jats:p>Between 2018 and 2023, WNV\u2010NAT positivity amongst Canadian blood donors remained stable, with no evidence of an increasing positivity trend. The utility of off\u2010season travel\u2010related testing may be limited, as no donors were identified during the six\u2010year study timeframe. Finally, confirmation testing using WNV\u2010specific PCR is recommended to identify true cases and to limit misidentification of other genetically similar viruses, such as JEV.<\/jats:p><\/jats:sec>","DOI":"10.1111\/trf.18326","type":"journal-article","created":{"date-parts":[[2025,6,28]],"date-time":"2025-06-28T03:24:17Z","timestamp":1751081057000},"page":"1484-1489","update-policy":"https:\/\/doi.org\/10.1002\/crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["West Nile Virus positivity amongst Canadian blood donors and effectiveness of off\u2010season screening"],"prefix":"10.1111","volume":"65","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-9129-5136","authenticated-orcid":false,"given":"Carmen L.","family":"Charlton","sequence":"first","affiliation":[{"name":"Microbiology, Donation Policy &amp; Studies, Canadian Blood Services  Edmonton Alberta Canada"},{"name":"Laboratory Medicine and Pathology University of Alberta  Edmonton Alberta Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2519-1109","authenticated-orcid":false,"given":"Steven J.","family":"Drews","sequence":"additional","affiliation":[{"name":"Microbiology, Donation Policy &amp; Studies, Canadian Blood Services  Edmonton Alberta Canada"},{"name":"Laboratory Medicine and Pathology University of Alberta  Edmonton Alberta Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kai","family":"Makowski","sequence":"additional","affiliation":[{"name":"National Microbiology Laboratory Public Health Agency of Canada  Winnipeg Manitoba Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Gordon","family":"Hawes","sequence":"additional","affiliation":[{"name":"Canadian Blood Services  Brampton Ontario Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Cynthia","family":"Cranney","sequence":"additional","affiliation":[{"name":"Canadian Blood Services  Brampton Ontario Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Alyssia","family":"Robinson","sequence":"additional","affiliation":[{"name":"National Microbiology Laboratory Public Health Agency of Canada  Winnipeg Manitoba Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Heidi","family":"Wood","sequence":"additional","affiliation":[{"name":"National Microbiology Laboratory Public Health Agency of Canada  Winnipeg Manitoba Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mark","family":"Bigham","sequence":"additional","affiliation":[{"name":"Canadian Blood Services  Vancouver British Columbia Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sheila F.","family":"O'Brien","sequence":"additional","affiliation":[{"name":"Epidemiology and Surveillance, Donation Policy &amp; Studies, Canadian Blood Services  Ottawa Ontario Canada"},{"name":"School of Epidemiology and Public Health University of Ottawa  Ottawa Ontario Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"311","published-online":{"date-parts":[[2025,6,28]]},"reference":[{"key":"e_1_2_10_2_1","unstructured":"International Committee on Taxonomy of Viruses.The ICTV Report on Virus Classification and Taxon Nomenclature.https:\/\/ictv.global\/report\/chapter\/flaviviridae\/flaviviridae\/orthoflavivirusAccessed October 23 2024."},{"key":"e_1_2_10_3_1","doi-asserted-by":"publisher","DOI":"10.1111\/trf.15744"},{"key":"e_1_2_10_4_1","doi-asserted-by":"publisher","DOI":"10.1006\/viro.2002.1449"},{"key":"e_1_2_10_5_1","unstructured":"Public Safety Canada.Timeline \u2013 CBSA Border Measures. Ottawa ON: PSC.2020https:\/\/www.publicsafety.gc.ca\/cnt\/trnsprnc\/brfng\u2010mtrls\/prlmntry\u2010bndrs\/20201119\/015\/index\u2010en.aspxAccessed October 23 2024."},{"key":"e_1_2_10_6_1","unstructured":"Public Health Agency of Canada.Government of Canada to remove COVID\u201019 border and travel measures effective October 1 [press release]. Ottawa ON: PHAC.2022. Accessed October 23 2024https:\/\/www.canada.ca\/en\/public\u2010health\/news\/2022\/09\/government\u2010of\u2010canada\u2010to\u2010remove\u2010covid\u201019\u2010border\u2010and\u2010travel\u2010measures\u2010effective\u2010october\u20101.html"},{"key":"e_1_2_10_7_1","doi-asserted-by":"publisher","DOI":"10.1186\/1756-3305-3-19"},{"key":"e_1_2_10_8_1","doi-asserted-by":"publisher","DOI":"10.2987\/5644.1"},{"key":"e_1_2_10_9_1","doi-asserted-by":"publisher","DOI":"10.1186\/s12889-023-15773-x"},{"key":"e_1_2_10_10_1","doi-asserted-by":"publisher","DOI":"10.1093\/jme\/tjz149"},{"key":"e_1_2_10_11_1","doi-asserted-by":"publisher","DOI":"10.3138\/canlivj-2023-0027"},{"key":"e_1_2_10_12_1","doi-asserted-by":"publisher","DOI":"10.1111\/JVH.13637"},{"key":"e_1_2_10_13_1","doi-asserted-by":"publisher","DOI":"10.1111\/LIV.15074"},{"key":"e_1_2_10_14_1","doi-asserted-by":"publisher","DOI":"10.4269\/ajtmh.13-0403"},{"key":"e_1_2_10_15_1","unstructured":"Centers for Disease Control and Prevention.West Nile Virus Historic Data (1999\u20132023).https:\/\/www.cdc.gov\/west-nile-virus\/data-maps\/historic-data.htmlAccessed October 23 2024."},{"key":"e_1_2_10_16_1","unstructured":"Public Health Agency of Canada.National case definition: West Nile Virus.https:\/\/www.canada.ca\/en\/public-health\/services\/diseases\/west-nile-virus\/health-professionals-treating-west-nile-virus\/national-case-definition.htmlAccessed October 23 2024."},{"key":"e_1_2_10_17_1","doi-asserted-by":"publisher","DOI":"10.1001\/jama.2021.15161"},{"key":"e_1_2_10_18_1","doi-asserted-by":"publisher","DOI":"10.1503\/cmaj.230249"}],"container-title":["Transfusion"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/pdf\/10.1111\/trf.18326","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,8,4]],"date-time":"2025-08-04T07:36:53Z","timestamp":1754293013000},"score":1,"resource":{"primary":{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/10.1111\/trf.18326"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2025,6,28]]},"references-count":17,"journal-issue":{"issue":"8","published-print":{"date-parts":[[2025,8]]}},"alternative-id":["10.1111\/trf.18326"],"URL":"https:\/\/doi.org\/10.1111\/trf.18326","archive":["Portico"],"relation":{},"ISSN":["0041-1132","1537-2995"],"issn-type":[{"value":"0041-1132","type":"print"},{"value":"1537-2995","type":"electronic"}],"subject":[],"published":{"date-parts":[[2025,6,28]]},"assertion":[{"value":"2024-10-23","order":0,"name":"received","label":"Received","group":{"name":"publication_history","label":"Publication History"}},{"value":"2025-06-17","order":2,"name":"accepted","label":"Accepted","group":{"name":"publication_history","label":"Publication History"}},{"value":"2025-06-28","order":3,"name":"published","label":"Published","group":{"name":"publication_history","label":"Publication History"}}]}}