Volume 99, Issue 2
  • ISSN: 0002-9637
  • E-ISSN: 1476-1645



Presently, few studies have investigated the role of domestic cats () in the recrudescence of flea-borne rickettsioses in California and the southern United States. In this study, we aimed to investigate the presence of or in domestic cats () and the fleas (primarily , the cat flea) associated with these cats in Riverside County, California. Thirty cats and 64 pools of fleas collected from these cats were investigated for rickettsial infections. Three cats and 17 flea pools (from 10 cats) tested positive for rickettsial infections. polymerase chain reaction and DNA sequencing indicated that one of the cats was positive for infections, whereas two were positive for senegalensis infection. In addition, 12 of the flea pools were positive for , whereas five were positive for senegalensis. By contrast, no cats or their associated fleas tested positive for . Finally, eight sera from these cats contained spotted fever group (SFGR) antibodies. The detection of and SFGR antibodies and the lack of and TGR antibodies support as the main rickettsial species infecting cat fleas. The detection of senegalensis in both fleas and cats also provides additional evidence that cats and their associated fleas are infected with other –like organisms highlighting the potential risk for human infections with or –like organisms.


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  • Received : 08 Sep 2017
  • Accepted : 11 Mar 2018
  • Published online : 04 Jun 2018

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