Molecular Detection of Tick-Borne Pathogens in Dogs from Indigenous Communities, Amazon, Brazil

Background: There are few reports of tick-borne pathogens infecting dogs living in indigenous communities of Brazil. Herein, we aimed to molecularly detect vector-borne pathogens in dogs from two indigenous communities in the Brazilian Amazon.Materials and Methods: We surveyed 327 dogs raised in Amazon region at 2 distinct indigenous ethnicities for the molecular detection of tick-borne pathogens (114 from Tapirape and 213 from Karaja indigenous ethnicity). Whole blood samples were subjected to PCR and sequencing for Ehrlichia, Babesia, and Hepatozoon. Univariate and multivariate analyses were used to investigate the factors affecting the pathogen infection patterns in dogs.Results: Among the 327 blood samples, 40 were positive for Ehrlichia canis (12.2%), 2 for Anaplasma platys (0.61%), and 204 were positive for Hepatozoon canis (66.5%). Binary Logistic Regression showed association between E. canis infection and ethnicity (p = 0.010) and tick attachment (p = 0.041). Karaja dogs were 3.4 times (95% CI 1.3-8.5) more likely to be positive for E. canis than Tapirape dogs. Dogs with ticks were 2.5 times more likely (95% CI 1.0-7.6) to be positive for E. canis than dogs without ticks.Conclusions: Our survey expands the knowledge regarding the presence of vector-borne pathogens in dogs from indigenous communities in the Amazon region.