Phylogeography of Rickettsia rickettsii Genotypes Associated with Fatal Rocky Mountain Spotted Fever

• DOI: 10.4269/ajtmh.14-0146
• Publication Date: 2014-06-24T06:03:11Z
• Authors: Christopher D. Pa...; Amy M. Denison; R. Ryan Lash; Lindy Liu; Brigid C. Bollweg; F. Scott Dahlgren; Cristina T. Kanamura; Rodrigo N. Angerami; Fabiana C. Pereir...; Roosecelis Brasil...; Sandor E. Karpathy
• Keywords: Rickettsia rickettsii; Intergenic region; Zoonosis

Rocky Mountain spotted fever (RMSF), a tick-borne zoonosis caused by Rickettsia rickettsii, is among the deadliest of all infectious diseases. To identify distribution various genotypes R. rickettsii associated with fatal RMSF, we applied molecular typing methods to samples DNA extracted from formalin-fixed, paraffin-embedded tissue specimens obtained at autopsy 103 case-patients seven countries who died RMSF. Complete sequences one or more intergenic regions were amplified tissues 30 (29%) and revealed consisting four distinct clades, including Hlp clade, regarded previously as non-pathogenic strain rickettsii. Distinct phylogeographic patterns identified when composite case-patient reference data mapped state country origin. The phylogeography likely determined ecological environmental factors that exist independently particular tick vector.