Krawczak, Felipe S.
Costa, Francisco B.
Labruna, Marcelo B.
Total Authors: 7
 Univ Sao Paulo, Dept Med Vet Prevent & Saude Anim, Sao Paulo - Brazil
 Inst Pesquisas Vet Desiderio Finamor IPVDF, Ctr Pesquisa Saude Anim, Eldorado Do Sul, RS - Brazil
 Univ Fed Goias, Escola Vet & Zootecnia, Setor Med Vet Prevent, Goiania, Go - Brazil
 Univ Estadual Maranhao, Dept Patol, Med Vet, Sao Luis, Maranhao - Brazil
 Univ Santo Amaro, Med & Bem Estar Anim, Sao Paulo, SP - Brazil
Total Affiliations: 5
VETERINARY PARASITOLOGY- REGIONAL STUDIES AND REPORTS;
Web of Science Citations:
In this work we performed a field study in a spotted fever-endemic area of the Pampa biome in Rio Grande do Sul, the southernmost state of Brazil (Rosario do Sul municipality), with the aim to evaluate the serological status of dogs for spotted fever group (SFG) rickettsiae, to attempt the isolation rickettsiae from A. tigrinum ticks, and to further perform a multi-genic molecular characterization of the rickettsial isolate. For this purpose, we collected blood serum samples and ticks from 18 rural dogs during 2016-2017. By immunofluorescence assay, all 18 dogs (100%) reacted serologically to SFG rickettsiae, with highest endpoint titers to R. parkeri, suggesting that at least part of these dogs have been infected by R. parkeri. Among 23 ticks collected from the dogs (13 A. tigrinum and 10 Rhipicephalus sanguineus sensu stricto), 46% (6/13) A. tigrinum contained DNA of R. parkeri, which was successfully isolated in Vero cell culture from one of these ticks. Partial sequences of five genes (gltA, ompA, virB4, dnaA, dnaK) and 3 intergenic spacers (mppA-purC, rrl-rrf-ITS, rpmE-tRNA(fMet)) were generated from this rickettsial isolate, and were all 100% identical to corresponding sequences of R. parkeri s.s. We provide the first report of a viable isolate of R. parkeri from A. tigrinum, confirming that this isolate belongs to the strain R. parkeri s.s., as it has already been demonstrated for other two tick species of the Amblyomma maculatum species complex (A. maculatum and Amblyomma triste). (AU)