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Abstract

In April 2025, a human seasonal reassortant influenza A(H1N2) virus with a 7:1 genetic constellation was detected in Sweden in a patient seeking primary care for influenza-like illness. The neuraminidase gene of this virus was from A(H3N2) and the remaining genes from A(H1N1)pdm09. The patient recovered. No additional cases have been detected through routine surveillance. This is so far the only identified A(H1N2) reassortant among three seasonal A(H1N1)pdm09 and A(H3N2) reassortants reported in GISAID from Europe during the 2024/25 season.

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/content/10.2807/1560-7917.ES.2025.30.31.2500542
2025-08-07
2025-08-30
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Novel influenza A(H1N2) seasonal reassortant virus identified in a patient, Sweden, April 2025
<p class="citation"> <span>Citation style for this article:</span> <span class="meta-value authors"> <a href="/search?value1=Dorina+Ujvari&option1=author&noRedirect=true" class="nonDisambigAuthorLink">Ujvari Dorina</a>, <a href="/search?value1=Tove+Samuelsson+Hagey&option1=author&noRedirect=true" class="nonDisambigAuthorLink">Samuelsson Hagey Tove</a>, <a href="/search?value1=AnnaSara+Carnahan&option1=author&noRedirect=true" class="nonDisambigAuthorLink">Carnahan AnnaSara</a>, <a href="/search?value1=Neus+Latorre-Margalef&option1=author&noRedirect=true" class="nonDisambigAuthorLink">Latorre-Margalef Neus</a></span>. Novel influenza A(H1N2) seasonal reassortant virus identified in a patient, Sweden, April 2025. <a href="/content/ecdc">Euro Surveill.</a> 2025;30(31):pii=2500542. <a href="https://doi.org/10.2807/1560-7917.ES.2025.30.31.2500542" title="doi link" target="_blank">https://doi.org/10.2807/1560-7917.ES.2025.30.31.2500542</a> <span class="ES_Article_citation"> <span class="generated">Received</span>: 23 Jul 2025;&nbsp;&nbsp; <span class="generated">Accepted</span>: 07 Aug 2025 </span> </p>
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