{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,21]],"date-time":"2026-09-21T06:02:14Z","timestamp":1789970534811,"version":"4.0.1"},"reference-count":49,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2026,9,21]],"date-time":"2026-09-21T00:00:00Z","timestamp":1789948800000},"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. Microbiol."],"abstract":"<jats:p>\n                    <jats:italic>Listeria monocytogenes<\/jats:italic>\n                    is a major concern in ready-to-eat (RTE) food production, particularly in cold-smoked salmon, which has been linked to several listeriosis outbreaks. This study investigated the occurrence and genetic diversity of\n                    <jats:italic>L. monocytogenes<\/jats:italic>\n                    within the pre-packaging area of an Italian cold-smoked salmon processing plant. From March 2023 to December 2023, 69 samples were collected, including 44 food contact surfaces (FCS), 15 non-food contact surfaces (NFCS), and 10 food samples (F). Microbiological analyses were conducted according to the standard qualitative method EN ISO 11290:2017, and suspected colonies were confirmed by MALDI-TOF mass spectrometry. Isolates were further characterized by multilocus sequence typing (MLST). As results, 18 samples showed the presence of\n                    <jats:italic>L. monocytogenes<\/jats:italic>\n                    , corresponding to an overall detection rate of 26.09%. The highest positivity rate was observed among NFCS (86.67%), followed by F (10%) and FCS (9.09%). MLST grouped isolates into five STs: ST5 (38.89%), ST9 (27.78%), ST6 (16.67%), ST7 (11.11%), ST14 (5.56%). ST5 and ST9 were the predominant STs and were repeatedly detected throughout the sampling period. These findings highlighted the importance of environmental monitoring, strengthened sanitation measures, and molecular typing to improve\n                    <jats:italic>L. monocytogenes<\/jats:italic>\n                    control in cold-smoked salmon processing plants.\n                  <\/jats:p>","DOI":"10.3389\/fmicb.2026.1917424","type":"journal-article","created":{"date-parts":[[2026,9,21]],"date-time":"2026-09-21T05:36:34Z","timestamp":1789968994000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":0,"title":["Listeria monocytogenes occurrence and genetic diversity within the pre-packaging area of an Italian cold-smoked salmon processing plant"],"prefix":"10.3389","volume":"17","author":[{"given":"Michela","family":"Berta","sequence":"first","affiliation":[{"name":"Department of Veterinary Sciences, University of Turin","place":["Grugliasco, TO, Italy"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Pierluigi","family":"Di Ciccio","sequence":"additional","affiliation":[{"name":"Department of Veterinary Sciences, University of Turin","place":["Grugliasco, TO, Italy"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Maria Teresa","family":"Bottero","sequence":"additional","affiliation":[{"name":"Department of Veterinary Sciences, University of Turin","place":["Grugliasco, TO, Italy"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Daniele","family":"Pattono","sequence":"additional","affiliation":[{"name":"Department of Veterinary Sciences, University of Turin","place":["Grugliasco, TO, Italy"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Giacomo","family":"Manacorda","sequence":"additional","affiliation":[{"name":"Department of Veterinary Sciences, University of Turin","place":["Grugliasco, TO, Italy"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Alessandra","family":"Dalmasso","sequence":"additional","affiliation":[{"name":"Department of Veterinary Sciences, University of Turin","place":["Grugliasco, TO, Italy"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1965","published-online":{"date-parts":[[2026,9,21]]},"reference":[{"key":"ref1","doi-asserted-by":"publisher","first-page":"109043","DOI":"10.1016\/j.ijfoodmicro.2021.109043","article-title":"Unraveling the emergence and population diversity of Listeria monocytogenes in a newly built meat facility through whole genome sequencing","volume":"340","author":"Alvarez-Molina","year":"2021","journal-title":"Int. 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Food Microbiol."},{"key":"ref9","doi-asserted-by":"crossref","first-page":"e0171389","DOI":"10.1371\/journal.pone.0171389","article-title":"Assessing the genome level diversity of Listeria monocytogenes from contaminated ice cream and environmental samples linked to a listeriosis outbreak in the United States","volume":"12","author":"Chen","year":"2017","journal-title":"PLoS One"},{"key":"ref10","year":"2018"},{"key":"ref11","year":"2018"},{"key":"ref12","year":"2023"},{"key":"ref13","year":"2024"},{"key":"ref14","doi-asserted-by":"publisher","first-page":"e02136","DOI":"10.1128\/aem.02136-21","article-title":"Whole-genome sequencing analysis of Listeria monocytogenes from rural, urban, and farm environments in Norway: genetic diversity, persistence, and relation to clinical and food isolates","volume":"88","author":"Fagerlund","year":"2022","journal-title":"Appl. Environ. Microbiol."},{"key":"ref15","doi-asserted-by":"publisher","first-page":"e00579-20","DOI":"10.1128\/aem.00579-20","article-title":"In-depth longitudinal study of Listeria monocytogenes ST9 isolates from the meat processing industry: resolving diversity and transmission patterns using whole-genome sequencing","volume":"86","author":"Fagerlund","year":"2020","journal-title":"Appl. Environ. Microbiol."},{"key":"ref16","doi-asserted-by":"crossref","first-page":"190","DOI":"10.1038\/s41597-022-01278-6","article-title":"A European-wide dataset to uncover adaptive traits of Listeria monocytogenes to diverse ecological niches","volume":"9","author":"F\u00e9lix","year":"2022","journal-title":"Sci. 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Food Prot."},{"key":"ref18","doi-asserted-by":"publisher","first-page":"3339","DOI":"10.3390\/foods12183339","article-title":"Listeria monocytogenes biofilms in food-associated environments: a persistent enigma","volume":"12","author":"Finn","year":"2023","journal-title":"Foods"},{"key":"ref19","doi-asserted-by":"crossref","DOI":"10.1016\/j.heliyon.2024.e27401","article-title":"Implementation of good manufacturing practices (GMP) to improve the quality of smoked fish (Scomber colias)","volume":"10","author":"Geraldo","year":"2024","journal-title":"Heliyon"},{"key":"ref20","doi-asserted-by":"publisher","first-page":"110093","DOI":"10.1016\/j.foodcont.2023.110093","article-title":"Environmental monitoring of three fresh-cut processing facilities reveals harborage sites for Listeria monocytogenes","volume":"155","author":"Gil","year":"2024","journal-title":"Food Control"},{"key":"ref21","doi-asserted-by":"crossref","first-page":"1543","DOI":"10.3390\/microorganisms11061543","article-title":"The slaughterhouse as hotspot of CC1 and CC6 Listeria monocytogenes strains with hypervirulent profiles in an integrated poultry chain of Italy","volume":"11","author":"Guidi","year":"2023","journal-title":"Microorganisms"},{"key":"ref22","doi-asserted-by":"crossref","first-page":"930895","DOI":"10.3389\/fmicb.2022.930895","article-title":"Atypical serogroup IVb-v1 of Listeria monocytogenes assigned to new ST2801, widely spread and persistent in the environment of a pork-meat producing plant of Central Italy","volume":"13","author":"Guidi","year":"2022","journal-title":"Front. 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Rep."},{"key":"ref26","doi-asserted-by":"publisher","first-page":"e00060","DOI":"10.1128\/cmr.00060-19","article-title":"Human listeriosis","volume":"36","author":"Koopmans","year":"2023","journal-title":"Clin. Microbiol. Rev."},{"key":"ref27","doi-asserted-by":"publisher","first-page":"1412","DOI":"10.3389\/fmicb.2020.01412","article-title":"Genomic characterization of Listeria monocytogenes isolated from ready-to-eat meat and meat processing environments in Poland","volume":"11","author":"Kurpas","year":"2020","journal-title":"Front. Microbiol."},{"key":"ref28","doi-asserted-by":"publisher","first-page":"49","DOI":"10.1515\/jvetres-2018-0007","article-title":"Ready-to-eat meat products as a source of Listeria monocytogenes","volume":"62","author":"Kurpas","year":"2018","journal-title":"J. Vet. 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Food Prot."},{"key":"ref36","doi-asserted-by":"publisher","first-page":"111604","DOI":"10.1016\/j.ijfoodmicro.2025.111604","article-title":"Controlling Listeria monocytogenes in the food processing environment: lessons learned from a salmon processor associated with outbreaks","volume":"449","author":"M\u00f8retr\u00f8","year":"2025","journal-title":"Int. J. Food Microbiol."},{"key":"ref37","doi-asserted-by":"publisher","first-page":"110482","DOI":"10.1016\/j.ijfoodmicro.2023.110482","article-title":"Genomic analysis of Listeria monocytogenes CC7 associated with clinical infections and persistence in the food industry","volume":"410","author":"M\u00f8retr\u00f8","year":"2024","journal-title":"Int. J. 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Microbiol."},{"key":"ref39","doi-asserted-by":"publisher","first-page":"1603","DOI":"10.3390\/microorganisms11061603","article-title":"Association of virulence, biofilm, and antimicrobial resistance genes with specific clonal complex types of Listeria monocytogenes","volume":"11","author":"Myintzaw","year":"2023","journal-title":"Microorganisms"},{"key":"ref40","doi-asserted-by":"publisher","first-page":"284","DOI":"10.3201\/eid2701.203266","article-title":"Listeriosis caused by persistence of Listeria monocytogenes serotype 4b sequence type 6 in cheese production environment","volume":"27","author":"N\u00fcesch-Inderbinen","year":"2021","journal-title":"Emerg. Infect. Dis."},{"key":"ref41","doi-asserted-by":"publisher","first-page":"866462","DOI":"10.3389\/fmicb.2022.866462","article-title":"Listeria monocytogenes\u2013how this pathogen survives in food-production environments?","volume":"13","author":"Osek","year":"2022","journal-title":"Front. 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Food Microbiol."},{"key":"ref45","doi-asserted-by":"publisher","first-page":"e9759","DOI":"10.2903\/j.efsa.2025.9759","volume":"23","year":"2025","journal-title":"EFSA J."},{"key":"ref46","doi-asserted-by":"publisher","first-page":"632","DOI":"10.1056\/NEJMoa1907462","article-title":"Outbreak of listeriosis in South Africa associated with processed meat","volume":"382","author":"Thomas","year":"2020","journal-title":"N. Engl. J. Med."},{"key":"ref47","doi-asserted-by":"publisher","first-page":"3910","DOI":"10.1111\/1541-4337.13219","article-title":"Listeria monocytogenes in food businesses: from persistence strategies to intervention\/prevention strategies\u2014a review","volume":"22","author":"Tuytschaever","year":"2023","journal-title":"Compr. Rev. Food Sci. Food Saf."},{"key":"ref48","doi-asserted-by":"crossref","first-page":"109962","DOI":"10.1016\/j.ijfoodmicro.2022.109962","article-title":"Deciphering the virulence potential of Listeria monocytogenes in the Norwegian meat and salmon processing industry by combining whole genome sequencing and in vitro data","volume":"383","author":"Wagner","year":"2022","journal-title":"Int. J. Food Microbiol."},{"key":"ref49","doi-asserted-by":"publisher","first-page":"4313","DOI":"10.1128\/AEM.02288-05","article-title":"One group of genetically similar Listeria monocytogenes strains frequently dominates and persists in several fish slaughter-and smokehouses","volume":"72","author":"Wulff","year":"2006","journal-title":"Appl. Environ. 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