Paddock Christopher D, Karpathy Sandor E, Henry Asa, Ryle Luke, Hecht Joy A, Hacker Jill K, Padgett Kerry A, Kjemtrup Anne M, Bullock Hannah, Lane Robert S, Ladner Jason T
Rickettsial Zoonoses Branch, Centers for Disease Control and Prevention, Atlanta, Georgia, USA.
The Pathogen and Microbiome Institute, Northern Arizona University, Flagstaff, Arizona, USA.
J Infect Dis. 2025 Apr 15;231(4):849-858. doi: 10.1093/infdis/jiae512.
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 >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.
太平洋海岸蜱热是一种症状较为严重的蜱传疾病，与落基山斑疹热（RMSF）相似。其病原体于1966年首次从加利福尼亚州采集的西方革蜱（太平洋海岸蜱）标本中分离出来。几十年来，这种细菌被模糊地鉴定为未分类的斑点热群立克次体物种364-D、立克次体364或菲利普立克次体。然而，这些名称都不符合正式细菌命名的标准。45多年前进行的小鼠血清分型研究以及几十年后的多位点序列分型数据表明，这种细菌与RMSF的病原体立氏立克次体分离株相似，但又有所不同。我们采用了一种综合分类方法，将表型、生态和临床数据与该病原体11个当代分离株的全基因组测序相结合，将其鉴定为立氏立克次体的一个独特亚种，并提出新名称立氏立克次体加利福尼亚亚种（Rickettsia rickettsii subsp californica subsp nov）。
