{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,15]],"date-time":"2026-09-15T06:04:23Z","timestamp":1789452263644,"version":"build-2803163510"},"reference-count":39,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2026,9,15]],"date-time":"2026-09-15T00:00:00Z","timestamp":1789430400000},"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":"\n The escalation of antimicrobial resistance (AMR) among critical-priority, extended-spectrum \u03b2-lactamase (ESBL)-producing pathogens poses a global public health threat. Applying a One Health framework, this study characterized CTX-M Group 1 gene variants alongside co-carried \u03b2-lactamase gene families (\n bla<\/jats:italic>\n OXA1 \u2212 like<\/jats:sub>\n ,\n bla<\/jats:italic>\n SHV<\/jats:sub>\n , and\n bla<\/jats:italic>\n TEM<\/jats:sub>\n ) in\n Enterobacterales<\/jats:italic>\n across the migratory shorebirds Little Stints (\n Calidris minuta<\/jats:italic>\n )\n -<\/jats:italic>\n livestock-aquatic interface in the Kenyan Rift Valley. Sampling occurred across two migratory cohorts-arrival from the Arctic and pre-departure from the lakes in a repeated cross-sectional eco-surveillance design across two contrasting environments: Lake Bogoria (low anthropogenic pressure) and Lake Magadi (high pressure). From 389 fecal and water samples (\n C. minuta, n<\/jats:italic>\n = 184; free-ranging domestic goats,\n n<\/jats:italic>\n = 157; water,\n n<\/jats:italic>\n = 48), 507 Gram-negative bacterial isolates were recovered, 479 of which were\n Enterobacterales<\/jats:italic>\n . Phenotypic ESBL screening identified 15.7% (75\/479) ESBL-positive\n Enterobacterales<\/jats:italic>\n from 68 samples (\n C. minuta, n<\/jats:italic>\n = 30; goats,\n n<\/jats:italic>\n = 30; water,\n n<\/jats:italic>\n = 8). Conventional polymerase chain reaction (PCR) of 79 isolates (75 phenotypic ESBL-\n Enterobacterales<\/jats:italic>\n producers and four ESBL-negative\n Klebsiella pneumoniae<\/jats:italic>\n controls\n )<\/jats:italic>\n detected CTX-M Group 1 variants in 14 isolates (13 ESBL-positive strains and one ESBL-negative\n K. pneumoniae<\/jats:italic>\n ). The CTX-M Group 1 variants were identified in\n Escherichia coli<\/jats:italic>\n (\n n<\/jats:italic>\n = 6),\n Enterobacter cloacae<\/jats:italic>\n (\n n<\/jats:italic>\n = 4),\n Klebsiella pneumoniae<\/jats:italic>\n (\n n<\/jats:italic>\n = 3), and\n Providencia rettgeri<\/jats:italic>\n (\n n<\/jats:italic>\n = 1), frequently co-harboring\n bla<\/jats:italic>\n OXA1 \u2212 like<\/jats:sub>\n ,\n bla<\/jats:italic>\n SHV<\/jats:sub>\n , and\n bla<\/jats:italic>\n TEM<\/jats:sub>\n gene families. Detection frequencies exhibited site-specific and temporal trajectories across domains. To our knowledge, this is the first PCR-based detection of CTX-M Group 1 variants in\n C. minuta<\/jats:italic>\n within this ecosystem. Rather than a mere passive corridor, the Kenyan Rift Valley serves as a dynamic ecological epicenter where global migratory flyways intersect with local anthropogenic drivers to modulate AMR. Despite the lack of sequencing data, this study provides vital baseline landscape data highlighting the need for sustained One Health-AMR surveillance and environmental stewardship.\n <\/jats:p>","DOI":"10.3389\/fmicb.2026.1893160","type":"journal-article","created":{"date-parts":[[2026,9,15]],"date-time":"2026-09-15T05:33:49Z","timestamp":1789450429000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":0,"title":["Surveillance of CTX-M group 1-producing Enterobacterales at the migratory Little Stint (Calidris minuta)\u2013goat\u2013aquatic interface in the Kenyan Rift Valley: a One Health approach"],"prefix":"10.3389","volume":"17","author":[{"given":"Catherine W.","family":"Mbuthia","sequence":"first","affiliation":[{"name":"Department of Veterinary Microbiology, Parasitology and Biotechnology, College of Veterinary Medicine and Biomedical Sciences, Sokoine University of Agriculture","place":["Morogoro, Tanzania"]},{"name":"Centre for Microbiology Research, Kenya Medical Research Institute","place":["Nairobi, Kenya"]},{"name":"SACIDS Foundation for One Health, Sokoine University of Agriculture","place":["Morogoro, Tanzania"]},{"name":"Department of Biological and Physical Sciences, School of Pure and Applied Sciences, Karatina University","place":["Karatina, Kenya"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Rael J.","family":"Too","sequence":"additional","affiliation":[{"name":"Centre for Microbiology Research, Kenya Medical Research Institute","place":["Nairobi, Kenya"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Alexanda","family":"Mzula","sequence":"additional","affiliation":[{"name":"Department of Veterinary Microbiology, Parasitology and Biotechnology, College of Veterinary Medicine and Biomedical Sciences, Sokoine University of Agriculture","place":["Morogoro, Tanzania"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Anita","family":"Chepkemei","sequence":"additional","affiliation":[{"name":"Centre for Microbiology Research, Kenya Medical Research Institute","place":["Nairobi, Kenya"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"John","family":"Kiiru","sequence":"additional","affiliation":[{"name":"Centre for Microbiology Research, Kenya Medical Research Institute","place":["Nairobi, Kenya"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Samuel","family":"Kariuki","sequence":"additional","affiliation":[{"name":"Centre for Microbiology Research, Kenya Medical Research Institute","place":["Nairobi, Kenya"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Abubakar S.","family":"Hoza","sequence":"additional","affiliation":[{"name":"Department of Veterinary Microbiology, Parasitology and Biotechnology, College of Veterinary Medicine and Biomedical Sciences, Sokoine University of Agriculture","place":["Morogoro, Tanzania"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1965","published-online":{"date-parts":[[2026,9,15]]},"reference":[{"key":"B1","doi-asserted-by":"publisher","first-page":"fiaa031","DOI":"10.1093\/femsec\/fiaa031","article-title":"Biofilms: hot spots of horizontal gene transfer (HGT) in aquatic environments, with a focus on a new HGT mechanism","volume":"96","author":"Abe","year":"2020","journal-title":"FEMS Microbiol. 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