Ticks and rickettsial infection in the wildlife of two regions of the Brazilian Amazon.

During 2009-2012, wild animals and their ticks were sampled in two areas within the Amazon biome of Brazil, in the states of Mato Grosso and Pará. Animal tissues, blood, and ticks were molecularly tested for Rickettsia and Coxiella DNA. A total of 182 wild animals were sampled, comprising 28 mammalian, five avian, and three reptilian species. Animal tissues or blood were all negative for Rickettsia or Coxiella DNA. A total of 454 ticks (22 larvae, 226 nymphs, 127 males, 79 females) were collected from 52 (28.6%) animals, and identified into 15 species: Amblyomma cajennense, A. naponense, A. humerale, A. nodosum, A. goeldii, A. oblongoguttatum, A. longirostre, A. calcaratum, A. coelebs, A. pacae, A. geayii, A. rotundatum, A. auricularium, A. ovale, and Haemaphysalis juxtakochi. While no Coxiella DNA was identified in ticks, six Rickettsia species were detected in the ticks. "Candidatus Rickettsia amblyommii" was the most common agent, detected in four tick species, A. cajennense, A. auricularium, A. longirostre, and A. humerale. The second most common agent, R. bellii, was detected in A. humerale and A. naponense. Rickettsia rhipicephali was detected in H. juxtakochi, and R. felis in A. humerale. Two possible new Rickettsia species were detected in A. naponense ticks, namely, a novel spotted fever group agent close-related to R. africae in Pará, and a novel Canadensis group agent in Mato Grosso. Results of the present study expand our knowledge on the tick fauna, and on the yet infantile knowledge of tick-borne rickettsiae in the Amazon biome.

Isolation and phylogenetic relationships of bat trypanosomes from different biomes in Mato Grosso, Brazil.

In the order Chiroptera, more than 30 trypanosome species belonging to the subgenera Herpetosoma, Schizotrypanum, Megatrypanum, and Trypanozoon have been described. The species Trypanosoma cruzi , Trypanosoma cruzi marinkellei, and Trypanosoma dionisii are the most common in bats and belong to the Schizotrypanum subgenus. Bats from 2 different biomes, Pantanal and Amazonia/Cerrado in the state of Mato Grosso, Brazil, were evaluated according to the presence of trypanosome parasites by means of hemoculture and PCR in primary samples (blood samples). A total of 211 bats from 20 different species were caught and the trypanosome prevalence, evaluated through hemoculture, was 9.0% (19), 15.5% (13), and 4.8% (6) in the municipalities of Confresa (Amazonia/Cerrado biome) and Poconé (Pantanal biome). Among the 123 primary samples obtained from the bats, only 3 (2.4%) were positive. Phylogenetic analysis using trypanosomatid barcoding (V7V8 region of SSU rDNA) identified all the isolates and primary samples as T. c. marinkellei. The sequences of the isolates were segregated according to the bat host genus or species and suggest that co-evolutionary patterns exist between hosts and parasites. Further studies in different Brazilian regions and biomes need to be conducted in order to gain real understanding of the diversity of trypanosomes in bats.

First Report of Trypanosoma sp. in Spectacled Caiman (Caiman crocodilus): Morphological and Phylogenetic Relationships.

In Crocodylidae family three trypanosomes species were described, T. grayi in African crocodilian and T. cecili and Trypanosoma sp. in Caimans species from Brazil. T. grayi was transmitted by tsetse flies and the vector of Brazilian caimans trypanosomes is unknown. We characterized first Brazilian trypanosome isolated in spectacled caiman (Caiman crocodilus) from Mato Grosso State in Brazil. Morphological findings in epimastigotes forms from axenic culture showed high similarity with Trypanosoma sp. described in Caiman yacare from Brazilian Pantanal. Phylogenetic studies performed with SSU rDNA and gGAPDH (glyceraldehydes-3-phosphato dehydrogenase glycosomal) clustering in T. grayi Clade and together to genotype Cay 01 from Trypanosoma unnamed species isolated in C. yacare. This is the first isolate of Trypanosoma sp. from C. crocodilus and the phylogenetic position with isolates in C. yacare from Pantanal region and demonstrates the low host specificity of cayman trypanosomes in Brazil.

Prevalence of anti- Neospora caninum and anti- Toxoplasma gondii antibodies in dogs from two different indigenous communities in the Brazilian Amazon Region.

Prevalence of Toxoplasma gondii and Neospora caninum antibodies in sera of 325 dogs in 11 villages inhabited by the Tapirapé and Karajá ethnic groups in the south of the Brazilian Amazon was determined by the use of an indirect fluorescence antibody test. Antibodies (cutoff 1:16) to T. gondii were found in 169 (52%) and to N. caninum (cut-off 1:50) in 32 (9.8%) of 325 dogs. Seropositivity for both parasitic infections was widely prevalent in dogs from these villages and was higher in older dogs, indicating post-natal transmission.