{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,29]],"date-time":"2026-09-29T06:23:05Z","timestamp":1790662985211,"version":"4.1.0"},"reference-count":50,"publisher":"Oxford University Press (OUP)","issue":"4","funder":[{"name":"State of Arizona Technology and Research Initiative Fund"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2025,4,15]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:p>The etiologic agent of Pacific Coast tick fever, a moderately severe tickborne illness that resembles Rocky Mountain spotted fever (RMSF), was first isolated in 1966 from specimens of Dermacentor occidentalis (the Pacific Coast tick) obtained in California. For several decades, this bacterium was identified ambiguously as the unclassified spotted fever group Rickettsia species 364-D, Rickettsia 364, or Rickettsia philipii. However, none of these epithets satisfied criteria of formal bacterial nomenclature. Data developed from mouse serotyping studies performed &amp;gt;45 years ago, and multilocus sequence typing several decades later, indicated that this bacterium was similar to, but distinct from, isolates of Rickettsia rickettsii, the etiological agent of RMSF. We applied an integrative taxonomic approach, combining phenotypic, ecological, and clinical data with whole-genome sequencing of 11 contemporary isolates of this pathogen to identify it as a distinct subspecies of R. rickettsii, and propose the name Rickettsia rickettsii subsp californica subsp nov.<\/jats:p>","DOI":"10.1093\/infdis\/jiae512","type":"journal-article","created":{"date-parts":[[2024,10,14]],"date-time":"2024-10-14T23:20:50Z","timestamp":1728948050000},"page":"849-858","source":"Crossref","is-referenced-by-count":8,"title":["<i>Rickettsia rickettsii<\/i>\n                    subsp\n                    <i>californica<\/i>\n                    subsp nov, the Etiologic Agent of Pacific Coast Tick Fever"],"prefix":"10.1093","volume":"231","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-1615-8526","authenticated-orcid":false,"given":"Christopher D","family":"Paddock","sequence":"first","affiliation":[{"name":"Rickettsial Zoonoses Branch, Centers for Disease Control and Prevention , Atlanta, Georgia ,","place":["USA"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sandor E","family":"Karpathy","sequence":"additional","affiliation":[{"name":"Rickettsial Zoonoses Branch, Centers for Disease Control and Prevention , Atlanta, Georgia ,","place":["USA"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Asa","family":"Henry","sequence":"additional","affiliation":[{"name":"The Pathogen and Microbiome Institute, Northern Arizona University , Flagstaff, Arizona ,","place":["USA"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Luke","family":"Ryle","sequence":"additional","affiliation":[{"name":"The Pathogen and Microbiome Institute, Northern Arizona University , Flagstaff, Arizona ,","place":["USA"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Joy A","family":"Hecht","sequence":"additional","affiliation":[{"name":"Rickettsial Zoonoses Branch, Centers for Disease Control and Prevention , Atlanta, Georgia ,","place":["USA"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jill K","family":"Hacker","sequence":"additional","affiliation":[{"name":"Center for Laboratory Sciences, California Department of Public Health , Richmond, California ,","place":["USA"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kerry A","family":"Padgett","sequence":"additional","affiliation":[{"name":"Center for Laboratory Sciences, California Department of Public Health , Richmond, California ,","place":["USA"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Anne M","family":"Kjemtrup","sequence":"additional","affiliation":[{"name":"Infectious Diseases Branch, California Department of Public Health , Sacramento, California ,","place":["USA"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hannah","family":"Bullock","sequence":"additional","affiliation":[{"name":"Infectious Diseases Pathology Branch, Centers for Disease Control and Prevention , Atlanta, Georgia ,","place":["USA"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Robert S","family":"Lane","sequence":"additional","affiliation":[{"name":"Department of Environmental Science, Policy and Management, University of California , Berkeley, California ,","place":["USA"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jason T","family":"Ladner","sequence":"additional","affiliation":[{"name":"The Pathogen and Microbiome Institute, Northern Arizona University , Flagstaff, Arizona ,","place":["USA"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"286","published-online":{"date-parts":[[2024,10,22]]},"reference":[{"key":"2026032414541839000_jiae512-B1","author":"Philip"},{"key":"2026032414541839000_jiae512-B2","first-page":"407","article-title":"Rocky Mountain spotted fever\u2014its prevalence and distribution in Modoc and Lassen counties, California\u2014a preliminary report","volume":"14","author":"Kelly","year":"2016","journal-title":"Calif State J Med"},{"key":"2026032414541839000_jiae512-B3","author":"Emmons"},{"key":"2026032414541839000_jiae512-B4","doi-asserted-by":"crossref","first-page":"287","DOI":"10.1093\/oxfordjournals.aje.a112301a","article-title":"Distribution of suspected tick vectors and reported cases of Rocky Mountain spotted fever in California","volume":"104","author":"Rotramel","year":"1976","journal-title":"Am. 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