title: Dynamics of Exposure to Rickettsia parkeri in Cattle in the Paraná River Delta, Argentina.
abstract: Several cases of human rickettsiosis caused by Rickettsia parkeri were recently documented in the Paraná River delta of Argentina, where the tick vector is Amblyomma triste Koch. As cattle suffer recurrent A. triste infestations, they are at risk of becoming infected with R. parkeri Herein we investigated the dynamics of R. parkeri and its A. triste vector in a herd of beef cattle. Cattle were followed for 18 mo and samples were analyzed for the presence of antibodies against four Rickettsia species (R. parkeri, Rickettsia bellii, Rickettsia amblyommii, and Rickettsia felis) and also for the presence of rickettsial DNA. Additionally, cattle were examined for attached ticks and questing adult ticks were collected. All ticks were analyzed for the presence of rickettsial DNA. No evidence of rickettsemia was found in any cow, but the high R. parkeri infection rate documented in A. triste both questing in the study area (13.9%) and feeding on cattle (19.8%) and the identification of antibodies against R. parkeri antigen in 90% of cattle are evidence that infection is taking place. Altogether, our data suggest that A. triste ticks are capable of naturally exposing cattle to R. parkeri However, the progress of R. parkeri infection and its impact on bovine health and production remain to be established.
authors.affiliation: Laboratorio de Ecología de Enfermedades, Instituto de Ciencias Veterinarias del Litoral (ICiVet-Litoral), Universidad Nacional del Litoral (UNL)/Consejo Nacional de Investigaciones Científicas y Tecnológicas (CONICET), Esperanza, Santa Fe, S3080, Argentina (lmonje@fcv.unl.edu.ar; valecc1983@hotmail.com; leandro_raul_antoniazzi@hotmail.com; pbeldome@fcv.unl.edu.ar), lmonje@fcv.unl.edu.ar.
authors.forename: L D
authors.initials: LD
authors.lastname: Monje
authors.affiliation: Departamento de Medicina Veterinária Preventiva e Saúde Animal, Faculdade de Medicina Veterinária e Zootecnia, São Paulo, 05508-270, Brazil (franc.borges@yahoo.com.br; labruna@usp.br).
authors.forename: F B
authors.initials: FB
authors.lastname: Costa
authors.affiliation: Laboratorio de Ecología de Enfermedades, Instituto de Ciencias Veterinarias del Litoral (ICiVet-Litoral), Universidad Nacional del Litoral (UNL)/Consejo Nacional de Investigaciones Científicas y Tecnológicas (CONICET), Esperanza, Santa Fe, S3080, Argentina (lmonje@fcv.unl.edu.ar; valecc1983@hotmail.com; leandro_raul_antoniazzi@hotmail.com; pbeldome@fcv.unl.edu.ar).
authors.forename: V C
authors.initials: VC
authors.lastname: Colombo
authors.affiliation: Departamento de Medicina Veterinária Preventiva e Saúde Animal, Faculdade de Medicina Veterinária e Zootecnia, São Paulo, 05508-270, Brazil (franc.borges@yahoo.com.br; labruna@usp.br).
authors.forename: M B
authors.initials: MB
authors.lastname: Labruna
authors.affiliation: Laboratorio de Ecología de Enfermedades, Instituto de Ciencias Veterinarias del Litoral (ICiVet-Litoral), Universidad Nacional del Litoral (UNL)/Consejo Nacional de Investigaciones Científicas y Tecnológicas (CONICET), Esperanza, Santa Fe, S3080, Argentina (lmonje@fcv.unl.edu.ar; valecc1983@hotmail.com; leandro_raul_antoniazzi@hotmail.com; pbeldome@fcv.unl.edu.ar).
authors.forename: L R
authors.initials: LR
authors.lastname: Antoniazzi
authors.affiliation: Instituto Nacional de Tecnología Agropecuaria, Estación Experimental San Pedro, B2930, Argentina (igamietea@yahoo.com), and.
authors.forename: I
authors.initials: I
authors.lastname: Gamietea
authors.affiliation: Instituto Nacional de Tecnología Agropecuaria, Estación Experimental Rafaela, S2300, Argentina (nava.santiago@inta.gob.ar).
authors.forename: S
authors.initials: S
authors.lastname: Nava
authors.affiliation: Laboratorio de Ecología de Enfermedades, Instituto de Ciencias Veterinarias del Litoral (ICiVet-Litoral), Universidad Nacional del Litoral (UNL)/Consejo Nacional de Investigaciones Científicas y Tecnológicas (CONICET), Esperanza, Santa Fe, S3080, Argentina (lmonje@fcv.unl.edu.ar; valecc1983@hotmail.com; leandro_raul_antoniazzi@hotmail.com; pbeldome@fcv.unl.edu.ar).
authors.forename: P M
authors.initials: PM
authors.lastname: Beldomenico
mesh_terms: D000818:Animals; D000907:Antibodies, Bacterial / Q000097:blood; D001096:Arachnid Vectors / Q000382:microbiology / Q000502:physiology; D001118:Argentina; D002417:Cattle; D002418:Cattle Diseases / Q000097:blood / Q000382:microbiology*; D026863:Ixodidae / Q000382:microbiology / Q000502:physiology; D012281:Rickettsia / Q000302:isolation & purification* / Q000502:physiology; D012282:Rickettsia Infections / Q000097:blood / Q000382:microbiology / Q000635:transmission / Q000662:veterinary*; D045483:Rivers / Q000382:microbiology*
chemical_list: D000907:Antibodies, Bacterial
keywords: Amblyomma triste; Argentina; Rickettsia parkeri; cattle