Determination of Rickettsial Agents in Dog Ticks by Polymerase Chain Reaction in Chile
Introduction
Rickettsial diseases like ehrlichiosis or anaplasmosis are emerging diseases with severe clinical signs including death. Ticks, their vector, transmit and infect their hosts, including dogs and humans. The aim of this study was to determine rickettsial agents in ticks from dogs of a rural area in Valparaiso district in Chile by PCR technique.
Methods
Ninety-three ticks and blood samples for EDTA were obtained from 30 dogs. For PCR technique, Rhipicephalus sanguineus (Rs) and Amblyomma tigrinum (At) were analyzed, grouped by species according to the dog extracted, using EHRout-1, EHRout-2, Ge2F and EHRL3-IP2 primers. The ELISA Snap 4DX Plus® was performed in serum from each dog.
Results
Twenty-five out of 30 dogs presented with ticks; 82 Rs and 11 At were identified. Two dogs presented with only At, 18 dogs with only Rs, and 5 dogs with both ticks. Anaplasma sp. was identified in A. tigrinum and R. sanguineus mixture from 8 and 1 dog, respectively; Ehrlichia sp. and R. andeanae were only identified in A. tigrinum mixture from 5 and 8 dogs, respectively. Eight dogs were Anaplasma sp. and 1 Ehrlichia sp. positive using the Snap 4Dx Plus®.
Conclusions
We found Anaplasma sp., Ehrlichia sp., and Rickettsia andeanae in the ticks from these rural dogs; R. sanguineus were PCR positive only to Anaplasma sp., while A. tigrinum presented the three rickettsial agents studied; only 3 out of 8 dogs presented serum and ticks positive to Anaplasma sp., while no match was found between serum and tick Ehrlichia sp. positive.