title: Serosurvey of antibodies against spotted fever group Rickettsia spp. in horse farms in Northern Paraná, Brazil.
abstract: Brazilian spotted fever (BSF) is an emerging disease most likely caused by Rickettsia rickettsii. The objective of the present study was to estimate the seroprevalence of BSF rickettsia infections in equines from six horse farms located in Londrina County, Paraná, Southern Brazil. Six owners of horse farms situated in Cambé, Santa Fé, Guaraci and Londrina municipalities participated in the study. All farms were located in areas where BSF has not been reported. A total of 273 horses were sampled and their sera were tested by indirect immunofluorescence assay (IFA) using R. rickettsii and R. parkeri antigens. Titers equal to and greater than 64 were considered positive. Of 273 sera tested, 15 (5.5%) reacted to R. rickettsii and 5 (1.8%) to R. parkeri. Five out of the six farms studied revealed seropositive animals and seropositivity rate ranged from 0 to 13%. The titers ranged from 64 to 512, and four samples had a titer of 512. Nine animals reacted to R. rickettsii with titers four-fold higher than those for R. parkeri. These results suggest that horses in Northern Paraná may have been exposed to rickettsiae identical or closely related to R. rickettsii.
authors.affiliation: Departamento de Medicina Veterinária Preventiva, Universidade Estadual de Londrina, Campus Universitário, Londrina-PR, Brazil.
authors.forename: Katia
authors.initials: K
authors.lastname: Tamekuni
authors.forename: Roberta dos Santos
authors.initials: Rdos S
authors.lastname: Toledo
authors.forename: Mauro de Freitas
authors.initials: Mde F
authors.lastname: Silva Filho
authors.forename: Valeska Bender
authors.initials: VB
authors.lastname: Haydu
authors.forename: Richard Campos
authors.initials: RC
authors.lastname: Pacheco
authors.forename: José Henrique
authors.initials: JH
authors.lastname: Cavicchioli
authors.forename: Marcelo Bahia
authors.initials: MB
authors.lastname: Labruna
authors.forename: John Stephen
authors.initials: JS
authors.lastname: Dumler
authors.forename: Odilon
authors.initials: O
authors.lastname: Vidotto
mesh_terms: D000818:Animals; D000907:Antibodies, Bacterial / Q000097:blood*; D001938:Brazil; D006734:Horse Diseases / Q000097:blood* / Q000453:epidemiology; D006736:Horses / Q000097:blood*; D012281:Rickettsia / Q000276:immunology*; D012282:Rickettsia Infections / Q000097:blood / Q000453:epidemiology / Q000662:veterinary*; D016036:Seroepidemiologic Studies
chemical_list: D000907:Antibodies, Bacterial