title: High prevalence of "Candidatus Rickettsia andeanae" and apparent exclusion of Rickettsia parkeri in adult Amblyomma maculatum (Acari: Ixodidae) from Kansas and Oklahoma.
abstract: Amblyomma maculatum (the Gulf Coast tick), an aggressive, human-biting, Nearctic and Neotropical tick, is the principal vector of Rickettsia parkeri in the United States. This pathogenic spotted fever group Rickettsia species has been identified in 8-52% of questing adult Gulf Coast ticks in the southeastern United States. To our knowledge, R. parkeri has not been reported previously from adult specimens of A. maculatum collected in Kansas or Oklahoma. A total of 216 adult A. maculatum ticks were collected from 18 counties in Kansas and Oklahoma during 2011-2014 and evaluated by molecular methods for evidence of infection with R. parkeri. No infections with this agent were identified; however, 47% of 94 ticks collected from Kansas and 73% of 122 ticks from Oklahoma were infected with "Candidatus Rickettsia andeanae" a spotted fever group Rickettsia species of undetermined pathogenicity. These preliminary data suggest that "Ca. R. andeanae" is well-adapted to survival in populations of A. maculatum in Kansas and Oklahoma, and that its ubiquity in Gulf Coast ticks in these states may effectively exclude R. parkeri from their shared arthropod host, which could diminish markedly or preclude entirely the occurrence of R. parkeri rickettsiosis in this region of the United States.
authors.affiliation: Rickettsial Zoonoses Branch, Centers for Disease Control and Prevention, Atlanta, GA, United States. Electronic address: CPaddock@cdc.gov.
authors.forename: Christopher D
authors.initials: CD
authors.lastname: Paddock
authors.affiliation: Infectious Diseases Pathology Branch, Centers for Disease Control and Prevention, Atlanta, GA, United States.
authors.forename: Amy M
authors.initials: AM
authors.lastname: Denison
authors.affiliation: Department of Diagnostic Medicine and Pathobiology, Kansas State University, KS, United States.
authors.forename: Michael W
authors.initials: MW
authors.lastname: Dryden
authors.affiliation: Department of Entomology and Plant Pathology, Oklahoma State University, Stillwater, OK, United States.
authors.forename: Bruce H
authors.initials: BH
authors.lastname: Noden
authors.affiliation: Travelers' Health Branch, Centers for Disease Control and Prevention, Atlanta, GA, United States.
authors.forename: R Ryan
authors.initials: RR
authors.lastname: Lash
authors.affiliation: Quillen College of Medicine, East Tennessee State University, Johnson City, TN, United States.
authors.forename: Sarah S
authors.initials: SS
authors.lastname: Abdelghani
authors.affiliation: Nell Hodgson Woodruff School of Nursing, Emory University, Atlanta, GA, United States.
authors.forename: Anna E
authors.initials: AE
authors.lastname: Evans
authors.affiliation: Bacterial Special Pathogens Branch, Centers for Disease Control and Prevention, Atlanta, GA, United States.
authors.forename: Aubree R
authors.initials: AR
authors.lastname: Kelly
authors.affiliation: Rickettsial Zoonoses Branch, Centers for Disease Control and Prevention, Atlanta, GA, United States.
authors.forename: Joy A
authors.initials: JA
authors.lastname: Hecht
authors.affiliation: Rickettsial Zoonoses Branch, Centers for Disease Control and Prevention, Atlanta, GA, United States.
authors.forename: Sandor E
authors.initials: SE
authors.lastname: Karpathy
authors.affiliation: Department of Diagnostic Medicine and Pathobiology, Kansas State University, KS, United States.
authors.forename: Roman R
authors.initials: RR
authors.lastname: Ganta
authors.affiliation: Veterinary Pathobiology, Oklahoma State University, Stillwater, OK, United States.
authors.forename: Susan E
authors.initials: SE
authors.lastname: Little
mesh_terms: D000818:Animals; D001096:Arachnid Vectors / Q000382:microbiology*; D005260:Female; D006801:Humans; D026863:Ixodidae / Q000382:microbiology*; D007615:Kansas / Q000453:epidemiology; D008297:Male; D009825:Oklahoma / Q000453:epidemiology; D015995:Prevalence; D012281:Rickettsia / Q000235:genetics / Q000302:isolation & purification*; D012282:Rickettsia Infections / Q000453:epidemiology*
keywords: Amblyomma maculatum; Rickettsia parkeri; Rickettsial interference; “Candidatus Rickettsia andeanae”