{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,24]],"date-time":"2026-08-24T06:19:17Z","timestamp":1787552357965,"version":"build-2736575974"},"reference-count":24,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2026,8,24]],"date-time":"2026-08-24T00:00:00Z","timestamp":1787529600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Capital\u2019 s Funds for Health Improvement and Research","award":["2024-2G-7106"],"award-info":[{"award-number":["2024-2G-7106"]}]}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Microbiol."],"abstract":"\n Background<\/jats:title>\n \n Aeromonas<\/jats:italic>\n species are ubiquitous aquatic bacteria that have emerged as significant foodborne enteric pathogens worldwide, yet their genomic landscape in clinical settings remains poorly delineated, particularly in Beijing.\n <\/jats:p>\n <\/jats:sec>\n \n Methods<\/jats:title>\n \n To address this gap, we performed active surveillance for\n Aeromonas<\/jats:italic>\n among 691 consecutive diarrheal outpatients in a Beijing district from January to December 2024. Isolates were recovered using enrichment culture coupled with PCR screening and identified by MALDI-TOF MS. Antimicrobial susceptibility was tested against 17 agents. Whole-genome sequencing was conducted on all isolates, enabling average nucleotide identity (ANI) analysis, comprehensive annotation of antimicrobial resistance and virulence genes, multilocus sequence typing (MLST), and core-genome SNP (cgSNP)-based phylogenetics.\n <\/jats:p>\n <\/jats:sec>\n \n Results<\/jats:title>\n \n Aeromonas<\/jats:italic>\n was detected in 3.3% (23\/691) of patients, with\n Aeromonas veronii<\/jats:italic>\n (56.52%, 13\/23) and\n Aeromonas caviae<\/jats:italic>\n (26.09%, 6\/23) predominating. Co-infections with other enteric pathogens occurred in 65.2% of positive cases. Resistance rates were notably high for ampicillin\/ampicillin-sulbactam (78.26%), nalidixic acid (56.52%), and ertapenem (21.73%), and 65.21% of isolates were multidrug-resistant. Genotypic\u2013phenotypic concordance was robust, with\n \u03b2<\/jats:italic>\n -lactamase genes\n ampS<\/jats:italic>\n (60.87%) and\n blaCEPH-A3<\/jats:italic>\n (47.83%) being most prevalent. Strikingly,\n mcr-3.25<\/jats:italic>\n and\n mcr-3.3<\/jats:italic>\n , which belong to the\n mcr<\/jats:italic>\n family (originally described as mobile colistin resistance genes), were identified in 8.70% of isolates, exhibiting perfect correlation with phenotypic resistance. Plasmer analysis suggested both\n mcr<\/jats:italic>\n genes to be chromosomally encoded. Comparative genomic analysis of virulence-associated genes revealed striking species-specific specialization:\n A. veronii<\/jats:italic>\n predominantly carried complete T3SS clusters (61.5%),\n A. caviae<\/jats:italic>\n and\n Aeromonas enteropelogenes<\/jats:italic>\n were enriched in T6SS genes, and a single\n A. dhakensis<\/jats:italic>\n isolate possessed an extensive arsenal including T3SS, T6SS, and a full RTX toxin cluster. MLST resolved the 23 isolates into 22 sequence types, 18 of which were novel. Phylogenetic reconstruction identified a tight monophyletic cluster of three\n A. veronii<\/jats:italic>\n isolates (9\u201327 SNP differences) recovered within a 96-h window, suggestive of a potential cluster that warrants further epidemiological investigation. Comparative genomic analysis of the rare species\n Aeromonas allosaccharophila<\/jats:italic>\n demonstrated that the Beijing clinical isolate S14 differs from the U.S. clinical strain ATCC 35942 by 42,099 SNPs, confirming its distinct genetic lineage.\n <\/jats:p>\n <\/jats:sec>\n \n Conclusion<\/jats:title>\n \n Collectively, this study delineates high genetic diversity, emerging chromosomal colistin resistance, and species-specific virulence specialization among\n Aeromonas<\/jats:italic>\n isolates from diarrheal patients in Beijing. The detection of a potential outbreak cluster and a rare clinical isolate underscores the power of genomics-based surveillance for detecting and mitigating foodborne pathogen thre\n ats<\/jats:italic>\n .\n <\/jats:p>\n <\/jats:sec>","DOI":"10.3389\/fmicb.2026.1909810","type":"journal-article","created":{"date-parts":[[2026,8,24]],"date-time":"2026-08-24T05:28:19Z","timestamp":1787549299000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":0,"title":["Genomic insights into Aeromonas infections in diarrheal patients: high diversity, emerging resistance, and potential outbreak in Beijing"],"prefix":"10.3389","volume":"17","author":[{"given":"Aixia","family":"Yan","sequence":"first","affiliation":[{"name":"Shunyi District Center for Disease Control and Prevention","place":["Beijing, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yuwei","family":"Liu","sequence":"additional","affiliation":[{"name":"Shunyi District Center for Disease Control and Prevention","place":["Beijing, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Shoufei","family":"Li","sequence":"additional","affiliation":[{"name":"Shunyi District Center for Disease Control and Prevention","place":["Beijing, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xinmiao","family":"Wu","sequence":"additional","affiliation":[{"name":"Shunyi District Center for Disease Control and Prevention","place":["Beijing, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jie","family":"Yang","sequence":"additional","affiliation":[{"name":"Shunyi District Center for Disease Control and Prevention","place":["Beijing, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yameng","family":"Gao","sequence":"additional","affiliation":[{"name":"Shunyi District Center for Disease Control and Prevention","place":["Beijing, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yu","family":"Zhao","sequence":"additional","affiliation":[{"name":"Shunyi District Center for Disease Control and Prevention","place":["Beijing, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Luotong","family":"Wang","sequence":"additional","affiliation":[{"name":"Shunyi District Center for Disease Control and Prevention","place":["Beijing, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Bo","family":"Pang","sequence":"additional","affiliation":[{"name":"National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention","place":["Beijing, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ying","family":"Li","sequence":"additional","affiliation":[{"name":"Shunyi District Center for Disease Control and Prevention","place":["Beijing, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1965","published-online":{"date-parts":[[2026,8,24]]},"reference":[{"key":"ref1","doi-asserted-by":"publisher","first-page":"1161","DOI":"10.3390\/pathogens14111161","article-title":"Aeromonas infections in humans-antibiotic resistance and treatment options","volume":"14","author":"Calvo S\u00e1nchez","year":"2025","journal-title":"Pathogens."},{"key":"ref3","doi-asserted-by":"publisher","first-page":"1285","DOI":"10.1128\/JCM.42.3.1285-1287.2004","article-title":"Type III secretion system genes in clinical Aeromonas isolates","volume":"42","author":"Chac\u00f3n","year":"2004","journal-title":"J. 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Updat."}],"container-title":["Frontiers in Microbiology"],"original-title":[],"link":[{"URL":"https:\/\/www.frontiersin.org\/articles\/10.3389\/fmicb.2026.1909810\/full","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,8,24]],"date-time":"2026-08-24T05:28:22Z","timestamp":1787549302000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.frontiersin.org\/articles\/10.3389\/fmicb.2026.1909810\/full"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,8,24]]},"references-count":24,"alternative-id":["10.3389\/fmicb.2026.1909810"],"URL":"https:\/\/doi.org\/10.3389\/fmicb.2026.1909810","relation":{},"ISSN":["1664-302X"],"issn-type":[{"value":"1664-302X","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,8,24]]},"article-number":"1909810"}}