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Phylogenetic reconstructions reveal an estimated 100-fold increase in chicken-to-wild-bird host transitions since 1900 compared to predomestication levels, alongside dramatic post-1960 expansions of chicken-associated lineages and rising pathogen effective population sizes. Model simulations further indicate that expanding, high-density chicken populations could act as ecological \u201cpathogen sponges,\u201d absorbing and amplifying diverse strains while sustaining high prevalence and coinfection rates. Genome-wide association analyses show that strains adapted to the chicken niche frequently acquire genes linked to oxidative stress, metal homeostasis, motility, and antimicrobial resistance. Together, these findings demonstrate that intensive poultry farming is reshaping pathogen ecology and accelerating the evolution and spread of a major zoonotic bacterium, with direct implications for human health.\n                  <\/jats:p>","DOI":"10.1073\/pnas.2609969123","type":"journal-article","created":{"date-parts":[[2026,7,27]],"date-time":"2026-07-27T19:47:21Z","timestamp":1785181641000},"update-policy":"https:\/\/doi.org\/10.1073\/pnas.cm10313","source":"Crossref","is-referenced-by-count":1,"title":["Accelerating\n                    <i>Campylobacter<\/i>\n                    zoonosis in the Anthropocene"],"prefix":"10.1073","volume":"123","author":[{"ORCID":"https:\/\/orcid.org\/0009-0003-9165-8966","authenticated-orcid":false,"given":"Oakem J.","family":"Kyne","sequence":"first","affiliation":[{"id":[{"id":"https:\/\/ror.org\/052gg0110","id-type":"ROR","asserted-by":"publisher"}],"name":"Ineos Oxford Institute for Antimicrobial Research, University of Oxford","place":["Oxford, United Kingdom"]},{"id":[{"id":"https:\/\/ror.org\/052gg0110","id-type":"ROR","asserted-by":"publisher"}],"name":"Department of Biology, Life and Mind Building, University of Oxford","place":["Oxford, United Kingdom"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9803-5209","authenticated-orcid":false,"given":"Bridget S.","family":"Penman","sequence":"additional","affiliation":[{"id":[{"id":"https:\/\/ror.org\/052gg0110","id-type":"ROR","asserted-by":"publisher"}],"name":"Department of Biology, Life and Mind Building, University of Oxford","place":["Oxford, United Kingdom"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0770-6845","authenticated-orcid":false,"given":"David J.","family":"Kelly","sequence":"additional","affiliation":[{"id":[{"id":"https:\/\/ror.org\/05krs5044","id-type":"ROR","asserted-by":"publisher"}],"name":"School of Biosciences, The University of Sheffield","place":["Sheffield, United Kingdom"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6901-3203","authenticated-orcid":false,"given":"Samuel K.","family":"Sheppard","sequence":"additional","affiliation":[{"id":[{"id":"https:\/\/ror.org\/052gg0110","id-type":"ROR","asserted-by":"publisher"}],"name":"Ineos Oxford Institute for Antimicrobial Research, University of Oxford","place":["Oxford, United Kingdom"]},{"id":[{"id":"https:\/\/ror.org\/052gg0110","id-type":"ROR","asserted-by":"publisher"}],"name":"Department of Biology, Life and Mind Building, University of Oxford","place":["Oxford, United Kingdom"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"341","published-online":{"date-parts":[[2026,7,27]]},"reference":[{"key":"e_1_3_4_1_2","doi-asserted-by":"publisher","DOI":"10.1126\/science.aad2622"},{"key":"e_1_3_4_2_2","doi-asserted-by":"publisher","DOI":"10.1073\/pnas.1711842115"},{"key":"e_1_3_4_3_2","volume-title":"Systema Naturae","author":"Linnaeus C.","year":"1758","unstructured":"C. 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