Candidatus ´Rickettsia andeanae´ in Amblyomma tigrinum, La Rioja (Argentina)

Abstract

This study aimed to molecularly detect species of the genus Rickettsia and the family Anaplasmataceae in ticks from La Rioja (Argentina). The fifty-nine ticks studied were collected from the environment and from humans from different neighborhoods of La Rioja capital, and from one dog from Villa Sanagasta town. They were identified as Rhipicephalus sanguineus sensu lato (48) and Amblyomma tigrinum (11). A female A. tigrinum, obtained from the dog, was positive for Rickettsia spp PCR. The amplified product could be sequenced and resulted in 100% identity with ´Candidatus Rickettsia andeanae’. As far as we know, this is the first study to detect microorganisms in ticks in La Rioja. In Argentina, ´Ca. R. andeanae’ was found in A. tigrinum from Tucumán and San Luis, in A. parvum from Córdoba and in A. parvum and A. pseudoconcolor from northeast Argentina. This Rickettsia species is currently considered to be of unknown pathogenicity for humans and animals. But we believe it necessary to continue and expand the studies on the tick species and their associated pathogens present in this region of Argentina.