Detection of Rickettsia felis in ectoparasites collected from domestic animals.

Ticks and fleas are arthropods widely distributed around the world involved in the transmission of various vector-borne diseases (VBDs), including Brazilian Spotted Fever (BSF), Baggio-Yoshinari Syndrome and the plague, with outstanding consequences for the public health. The aim of this study was to investigate the presence of Rickettsia spp., Borrelia spp. and Yersinia pestis in arthropods collected from dogs, cats and horses living in the state of Pernambuco, Northeastern Brazil. From January 2017 to April 2019, ectoparasites were collected, morphologically identified and molecularly analysed through PCR and sequencing. In total 401 specimens were collected from 86 animals, being 68% (n = 273) and 32% (n = 128) from rural and urban areas, respectively. The most commonly detected species were the ticks Dermacentor nitens, Amblyomma sculptum, Rhipicephalus sanguineus sensu lato (s.l.), Rhipicephalus microplus, and Amblyomma ovale, and the fleas Ctenocephalides felis and Ctenocephalides canis. DNA of Rickettsia felis was detected in D. nitens collected from horses, and C. felis, and R. sanguineus s.l. collected from dogs. All samples scored negative for Borrelia spp. and Y. pestis DNA. This study provides valuable data on ectoparasite fauna from domestic animals and identifies the circulation of a zoonotic pathogen (i.e., R. felis) in the population of the arthropods assessed. Therefore, preventive measures should be adopted in order to reduce the risk of occurrence of neglected VBD caused by this pathogen in animal and human hosts.