First Detection of Rickettsia typhi and Rickettsia felis in Fleas Collected From Client-Owned Companion Animals in the Southern Great Plains

Flea-borne rickettsiosis occurs worldwide and includes a number of pathogens, namely, Rickettsia typhi and Rickettsia felis. Most studies in the United States have occurred in southern Texas and California where flea-borne rickettsiosis is endemic, resulting in a lack of information from other regions of the country. Between March and August 2016, 222 fleas were collected from 52 client-owned dogs and cats in two urban areas in Oklahoma. Fleas were identified using morphological characteristics then pooled and tested by polymerase chain reaction (PCR) using published primers for gltA, ompB, and 17-kDa. The majority (98.6%) of fleas collected were Ctenocephalides felis (Bouche) followed by Pulex irritans (L) (1.4%). Overall, fleas collected from 30.0% (6/20) cats and 43.8% (14/32) dogs were infected with R. felis. Three C. felis-pools collected from three dogs, two in the Enid area (central Oklahoma) and one in the Elk City area (western Oklahoma), were infected with R. typhi as well as R. felis. 'Candidatus R. senegalensis' was detected in one pool of fleas taken from a cat in Oklahoma City. This is the first evidence that flea-borne Rickettsia species occur in fleas obtained from client-owned dogs and cats in the Great Plains region. The impact of these Rickettsia species on public health in the region needs further investigation.