1. Phylogeography of Rickettsia rickettsii genotypes associated with fatal Rocky Mountain spotted fever.
- Author
-
Paddock CD, Denison AM, Lash RR, Liu L, Bollweg BC, Dahlgren FS, Kanamura CT, Angerami RN, Pereira dos Santos FC, Brasil Martines R, and Karpathy SE
- Subjects
- Adolescent, Adult, Aged, Americas epidemiology, Animals, Child, Child, Preschool, DNA, Bacterial chemistry, DNA, Bacterial genetics, DNA, Intergenic, Female, Genotype, Humans, Infant, Male, Middle Aged, Molecular Typing, Phylogeography, Rickettsia rickettsii classification, Rocky Mountain Spotted Fever epidemiology, Rocky Mountain Spotted Fever mortality, Rocky Mountain Spotted Fever pathology, Sequence Analysis, DNA, Young Adult, Rickettsia rickettsii genetics, Rocky Mountain Spotted Fever microbiology
- Abstract
Rocky Mountain spotted fever (RMSF), a tick-borne zoonosis caused by Rickettsia rickettsii, is among the deadliest of all infectious diseases. To identify the distribution of various genotypes of R. rickettsii associated with fatal RMSF, we applied molecular typing methods to samples of DNA extracted from formalin-fixed, paraffin-embedded tissue specimens obtained at autopsy from 103 case-patients from seven countries who died of RMSF. Complete sequences of one or more intergenic regions were amplified from tissues of 30 (29%) case-patients and revealed a distribution of genotypes consisting of four distinct clades, including the Hlp clade, regarded previously as a non-pathogenic strain of R. rickettsii. Distinct phylogeographic patterns were identified when composite case-patient and reference strain data were mapped to the state and country of origin. The phylogeography of R. rickettsii is likely determined by ecological and environmental factors that exist independently of the distribution of a particular tick vector., (© The American Society of Tropical Medicine and Hygiene.)
- Published
- 2014
- Full Text
- View/download PDF