title: Two pathogens and one disease: detection and identification of flea-borne Rickettsiae in areas endemic for murine typhus in California.
abstract: Results of an environmental assessment conducted in a newly emergent focus of murine typhus in southern California are described. Opossums, Didelphis virginiana Kerr, infested with cat fleas, Ctenocephalides felis Buché, in the suburban area were abundant. Animal and flea specimens were tested for the DNA of two flea-borne rickettsiae, Rickettsia typhi and Rickettsia felis. R. felis was commonly detected in fleas collected throughout this area while R. typhi was found at a much lower prevalence in the vicinity of just 7 of 14 case-patient homes identified. DNA of R. felis, but not R. typhi, was detected in renal, hepatic, and pulmonary tissues of opossums. In contrast, there were no hematologic polymerase chain reaction findings of R. felis or R. typhi in opossums, rats, and cats within the endemic area studied. Our data suggest a significant probability of human exposure to R. felis in the area studied; however, disease caused by this agent is not recognized by the medical community and may be misdiagnosed as murine typhus using nondiscriminatory serologic methods.
authors.affiliation: Division of Vector-borne Diseases, Vector-Borne Diseases, CDC, Atlanta, GA 30333, USA.
authors.forename: Marina E
authors.initials: ME
authors.lastname: Eremeeva
authors.forename: Sandor E
authors.initials: SE
authors.lastname: Karpathy
authors.forename: Laura
authors.initials: L
authors.lastname: Krueger
authors.forename: Erica K
authors.initials: EK
authors.lastname: Hayes
authors.forename: Ashley M
authors.initials: AM
authors.lastname: Williams
authors.forename: Yamitzel
authors.initials: Y
authors.lastname: Zaldivar
authors.forename: Stephen
authors.initials: S
authors.lastname: Bennett
authors.forename: Robert
authors.initials: R
authors.lastname: Cummings
authors.forename: Art
authors.initials: A
authors.lastname: Tilzer
authors.forename: Robert K
authors.initials: RK
authors.lastname: Velten
authors.forename: Nelson
authors.initials: N
authors.lastname: Kerr
authors.forename: Gregory A
authors.initials: GA
authors.lastname: Dasch
authors.forename: Renjie
authors.initials: R
authors.lastname: Hu
mesh_terms: D000818:Animals; D002140:California / Q000453:epidemiology; D002415:Cats; D019353:Endemic Diseases; D005260:Female; D006801:Humans; D008297:Male; D051379:Mice; D009893:Opossums; D051381:Rats; D041161:Rickettsia felis / Q000302:isolation & purification*; D012286:Rickettsia typhi / Q000302:isolation & purification*; D005423:Siphonaptera / Q000382:microbiology*; D014437:Typhus, Endemic Flea-Borne / Q000453:epidemiology / Q000382:microbiology*