Two Pathogens and One Disease: Detection and Identification of Flea-Borne Rickettsiae in Areas Endemic for Murine Typhus in California (original) (raw)

2012, Journal of Medical Entomology

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 ßeas, Ctenocephalides felis Buché , in the suburban area were abundant. Animal and ßea specimens were tested for the DNA of two ßea-borne rickettsiae, Rickettsia typhi and Rickettsia felis. R. felis was commonly detected in ßeas 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 identiÞed. 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 Þndings of R. felis or R. typhi in opossums, rats, and cats within the endemic area studied. Our data suggest a signiÞcant 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. KEY WORDS ßea-borne rickettsiosis, Rickettsia typhi, Rickettsia felis, ßea, opossum The Þndings and conclusions in this report are those of the authors and do not necessarily represent the views of the Centers for Disease Control or the Department of Health and Human Services of the United States.