Rickettsia felis in Rhipicephalus sanguineus from Two Distant Chilean Cities

Introduction: Rickettsia felis is an emerging agent considered a human threat; although its natural reservoir and agent of transmission is the cat flea, it has been also found in other vectors. R. felis has been identified in Chile in cat fleas and in one specimen of Rhipicephalus sanguineus collected in the Metropolitan Region. The objective of this study was to detect the presence of Rickettsia spp. in R. sanguineus from dogs of two different and distant geographical areas in Chile. Material and Methods: We performed a domiciliary sampling in urban and rural localities of two distant areas of the country-the Metropolitan Region in the center and the northern city of Arica. A total of 460 households were visited; one dog per household was included in the study and ectoparasites were collected from them. Results: R. sanguineus was found in 50% of the 460 dogs. R. felis was identified by amplification and sequencing of gltA, ompA, and ompB genes in R. sanguineus from both regions, with predominance in Arica. Discussion: The presence of R. felis in R. sanguineus from two distant regions of Chile suggests that this rickettsial agent is well established in the country. Considering that no human spotted fever group infections have been recognized in the country, the results should alert clinicians about such possible cases. The role of R. sanguineus in the epidemiology and transmission of R. felis should be further investigated.