Seroprevalence of Tick-Borne Pathogens and Tick Infestation in Dogs from Tapirape and Karaja Indigenous Communities, Brazil

With the aim of studying some tick-borne diseases, a total of 327 dogs (114 from Tapirape and 213 from Karaja indigenous ethnicity, Mato Grosso, MT, Brazil) were sampled. Serum samples were submitted to the indirect fluorescence antibody test (IFAT) to detect antibodies against Babesia vogeli, Ehrlichia canis, and Rickettsia spp. Possible associations of risk factors and the occurrence of seroreativity to tick-borne agents and tick infestations were analyzed through chi-squared tests. Among 327 dogs, 46 (13.15%) were seropositive for B. vogeli and 47 (14.37%) for E. canis. The B. vogeli seroprevalence was higher for Karaja and for adult dogs (p>0.05). No association was found for E. canis seroprevalence. From 103 serum samples tested with rickettsial antigens, 90 (87%) dogs were seropositive to Rickettsia spp., with highest reactivity to Rickettsia amblyommii. Canine seropositivity to Rickettsia spp. was associated (p<0.05) with ethnicity (higher seroprevalence in Tapirape dogs), age (higher in adults), and hunting (higher among hunting dogs). From the 327 dogs, 39 (11.9%) were infested by ticks (Amblyomma cajennense sensu stricto, Amblyomma ovale, Amblyomma oblongoguttatum, Amblyomma tigrinum, and Rhipicephalus sanguineus). Infestations by Amblyomma spp. ticks were higher in dogs from Tapirape community and in hunting dogs (p<0.05). Regarding R. sanguineus, infestations were higher (p<0.05) among young dogs.