title: Survey of canine tick-borne diseases in Lábrea, Brazilian Amazon: 'accidental' findings of Dirofilaria immitis infection.
abstract: Blood samples were collected from 99 domestic dogs from the urban and rural areas of the Lábrea municipality, state of Amazonas, Brazil. Canine serum samples were tested by immunofluorescence assay against Rickettsia spp., which revealed that only 3.0% (1/33) and 7.6% (5/66) of the dogs from urban and rural areas, respectively, reacted positively to at least one Rickettsia species. DNA was extracted from canine blood and tested by a battery of PCR assays targeting protozoa of the genera Babesia and Hepatozoon, and bacteria of the genera Rickettsia and Ehrlichia and family Anaplasmataceae. All samples were negative in the PCR assays targeting the genera Babesia, Hepatozoon, Ehrlichia and Rickettsia. For Anaplasmataceae, 3% (1/33) and 39.4% (26/66) of the urban and rural dogs, respectively, yielded amplicons that generated DNA sequences 100% identical to the corresponding sequence of Wolbachia endosymbiont of Dirofilaria immitis. Because of these results, all canine DNA samples were further tested in a PCR assay targeting filarial nematodes, which was positive for 18.2% (6/33) and 57.6% (38/66) urban and rural dogs, respectively. Filarial-PCR products generated DNA sequences 100% identical to D. immitis. While tick-borne infections were rare in Lábrea, D. immitis infection rates were among the highest reported in South America.
authors.affiliation: Departamento de Medicina Veterinária Preventiva e Saúde Animal, Faculdade de Medicina Veterinária e Zootecnia, Universidade de São Paulo - USP, São Paulo, SP, Brasil.
authors.forename: Herbert Sousa
authors.initials: HS
authors.lastname: Soares
authors.affiliation: Faculdades São Lucas - FSL, Porto Velho, RO, Brasil.
authors.forename: Luis Marcelo Aranha
authors.initials: LM
authors.lastname: Camargo
authors.affiliation: Departamento de Medicina Veterinária Preventiva e Saúde Animal, Faculdade de Medicina Veterinária e Zootecnia, Universidade de São Paulo - USP, São Paulo, SP, Brasil.
authors.forename: Solange Maria
authors.initials: SM
authors.lastname: Gennari
authors.affiliation: Departamento de Medicina Veterinária Preventiva e Saúde Animal, Faculdade de Medicina Veterinária e Zootecnia, Universidade de São Paulo - USP, São Paulo, SP, Brasil.
authors.forename: Marcelo Bahia
authors.initials: MB
authors.lastname: Labruna
mesh_terms: D000818:Animals; D001938:Brazil / Q000453:epidemiology; D004184:Dirofilariasis / Q000453:epidemiology*; D004283:Dog Diseases / Q000453:epidemiology* / Q000469:parasitology*; D004285:Dogs; D005260:Female; D033162:Incidental Findings; D008297:Male; D017282:Tick-Borne Diseases / Q000453:epidemiology / Q000662:veterinary*