{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,8]],"date-time":"2026-09-08T05:10:05Z","timestamp":1788844205965,"version":"build-2803163510"},"reference-count":39,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2026,9,7]],"date-time":"2026-09-07T00:00:00Z","timestamp":1788739200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Public Health"],"abstract":"<jats:sec>\n                    <jats:title>Background<\/jats:title>\n                    <jats:p>Genomic sequencing can complement routine influenza surveillance by enabling clade-level characterization of selected specimens and the genomic characterization of mixed viral specimens. This descriptive laboratory-based study characterized influenza A-positive respiratory specimens collected through routine surveillance in the Republic of Moldova and selected for sequencing.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>Between October 2025 and February 2026, 1,081 respiratory specimens were screened by multiplex real-time reverse transcription polymerase chain reaction for influenza A, influenza B, and SARS-CoV-2. Of 291 influenza A-positive specimens, 174 had cycle-threshold values \u226427, and 38 were selected for hybrid-capture sequencing based on repeat cycle-threshold values and technical suitability. Consensus sequences were analyzed with Nextclade, and the SARS-CoV-2 component of one mixed specimen was additionally assessed using Pangolin.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>\n                      All 38 selected specimens yielded analyzable influenza A hemagglutinin sequences, with hemagglutinin-segment coverage ranging from 87.6% to 100%. The dataset comprised 32 A(H3N2) specimens, five A(H1N1)pdm09 specimens, and one mixed A(H1N1)pdm09\/SARS-CoV-2 specimen. All A(H3N2) hemagglutinin sequences were assigned to clade K, subclade 2a.3a.1. The six A(H1N1)pdm09 hemagglutinin components were assigned to clade D.3.1 (\n                      <jats:italic>n<\/jats:italic>\n                      = 2) or D.3.1.1 (\n                      <jats:italic>n<\/jats:italic>\n                      = 4). The SARS-CoV-2 consensus was assigned to Nextclade clade 25I; poor overall sequence quality limited confidence in fine-scale lineage assignment and precluded robust interpretation of private mutations.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusion<\/jats:title>\n                    <jats:p>The study provides a descriptive genomic characterization of a laboratory-selected subset and illustrates a workflow linking molecular testing to sequencing. The findings should not be interpreted as estimates of national clade prevalence, geographical distribution, or A(H1N1)pdm09\/SARS-CoV-2 co-infection frequency.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.3389\/fpubh.2026.1913939","type":"journal-article","created":{"date-parts":[[2026,9,8]],"date-time":"2026-09-08T04:23:41Z","timestamp":1788841421000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":0,"title":["Genomic characterization of selected influenza A-positive specimens and an A(H1N1)pdm09\/SARS-CoV-2 co-infection in the Republic of Moldova"],"prefix":"10.3389","volume":"14","author":[{"given":"Svetlana","family":"Colac","sequence":"first","affiliation":[{"name":"National Agency for Public Health","place":["Chisinau, Moldova"]},{"name":"Nicolae Testemitanu State University of Medicine and Pharmacy","place":["Chisinau, Moldova"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Valeria","family":"Ceban","sequence":"additional","affiliation":[{"name":"National Agency for Public Health","place":["Chisinau, Moldova"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Livia","family":"\u021aapu","sequence":"additional","affiliation":[{"name":"National Agency for Public Health","place":["Chisinau, Moldova"]},{"name":"Nicolae Testemitanu State University of Medicine and Pharmacy","place":["Chisinau, Moldova"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Veronica","family":"Burlac","sequence":"additional","affiliation":[{"name":"National Agency for Public Health","place":["Chisinau, Moldova"]},{"name":"Nicolae Testemitanu State University of Medicine and Pharmacy","place":["Chisinau, Moldova"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Nicolae","family":"Jelamschi","sequence":"additional","affiliation":[{"name":"National Agency for Public Health","place":["Chisinau, Moldova"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Olga","family":"Burduniuc","sequence":"additional","affiliation":[{"name":"National Agency for Public Health","place":["Chisinau, Moldova"]},{"name":"Nicolae Testemitanu State University of Medicine and Pharmacy","place":["Chisinau, Moldova"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1965","published-online":{"date-parts":[[2026,9,7]]},"reference":[{"key":"ref1","volume-title":"Influenza (seasonal)","year":"2025"},{"key":"ref2","volume-title":"Implementing the Integrated Sentinel Surveillance of influenza and other Respiratory Viruses of Epidemic and Pandemic Potential by the Global Influenza Surveillance and Response System: Standards and Operational Guidance","year":"2024"},{"key":"ref3","volume-title":"Global Genomic Surveillance Strategy for Pathogens with Pandemic and Epidemic Potential, 2022\u20132032","year":"2022"},{"key":"ref4","volume-title":"Reporting Protocol for Integrated Respiratory Virus Surveillance, Version 1.1","year":"2026"},{"key":"ref5","doi-asserted-by":"publisher","first-page":"12","DOI":"10.38045\/ohrm.2024.3.02","article-title":"Evolution of influenza and acute respiratory infections in the Republic of Moldova during the 2014\/15 to 2022\/23 epidemic seasons","volume":"5","author":"Druc","year":"2024","journal-title":"One Health Risk Manag"},{"key":"ref6","first-page":"85","article-title":"Genetic significance and monitoring of circulating variants of the SARS-CoV-2 virus in the Republic of Moldova","volume":"2","author":"Colac","year":"2023","journal-title":"One Health Risk Manag"},{"key":"ref7","first-page":"152","article-title":"Variabilitatea genetic\u0103 a virusului SARS-CoV-2, varianta omicron circulante pe teritoriul Republicii Moldova \/ genetic variability of the omicron variant of the SARS-CoV-2 virus circulating in the territory of the Republic of Moldova","volume":"10","author":"Colac","year":"2023","journal-title":"Revista de \u0218tiin\u021be ale S\u0103n\u0103t\u0103\u021bii din Moldova"},{"key":"ref8","first-page":"136","article-title":"Analiza diversit\u0103\u0163ii genetice a virusului SARS-CoV-2: revista literaturii","author":"Colac","year":"2024","journal-title":"One Health Risk Manag"},{"key":"ref9","doi-asserted-by":"publisher","first-page":"16","DOI":"10.38045\/ohrm.2025.1.02","article-title":"Genetic diversity analysis of the SARS-CoV-2 virus: a literature review","volume":"6","author":"Colac","year":"2025","journal-title":"One Health Risk Manag"},{"key":"ref10","doi-asserted-by":"publisher","first-page":"11","DOI":"10.5281\/zenodo.15879875","article-title":"Genomic monitoring of SARS-CoV-2 variants in the Republic of Moldova","volume":"94","author":"Colac","year":"2025","journal-title":"Arta Med"},{"key":"ref11","first-page":"280","volume-title":"Patrimoniul cultural de ieri \u2013 implica\u0163ii \u00een dezvoltarea societ\u0103\u0163ii durabile de m\u00e2ine. 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