Sharing of living area and exposure of domestic and wild canids to ticks,Rickettsia parkeri andRangelia vitalii in the Atlantic Forest of southern Brazil

Author(s)

de Souza Jr, Julio C. ; de Oliveira, Karina H. L. ; Gruener, Cintia G. ; Barbieri, Amalia R. M. ; Martins, Thiago F. ; Soares, Joao F. ; Labruna, Marcelo B.

• Document type: Journal article
• Source: VETERINARY PARASITOLOGY- REGIONAL STUDIES AND REPORTS; v. 43, p. 5-pg., 2023-08-01.

Abstract

Spotted fever caused by the bacterium Rickettsia parkeri, and canine rangeliosis caused by the protozoan Rangelia vitalii, are emerging or re-emerging tick-borne diseases in Brazil, where the main tick vectors are Amblyomma ovale and Amblyomma aureolatum, respectively. In the present study, we evaluated exposure to R. parkeri and R. vitalii infection among domestic (Canis lupus familiaris) and wild (Cerdocyon thous) canids sharing living areas within an Atlantic Forest area of southern Brazil. Four different domestic dogs and three different wild canids were captured. Most of the ticks collected from either domestic or wild canids were identified as A. ovale and A. aureolatum. DNA of R. parkeri was amplified from 14% of the A. ovale specimens. Two domestic dogs and two wild canids were seroreactive to R. parkeri antigens with high endpoint titers (>1024). Rangelia vitalii DNA was detected in two wild canids; one of them was resampled 93 days later, again infected by R. vitalii. We report exposure/infection of domestic dogs and wild canids to R. vitalii and/or R. parkeri-infected ticks in an Atlantic Forest area shared by both canid species, indicating that they also shared the same populations of the tick vectors, A. aureolatum and A. ovale. While A. ovale, A. aureolatum, R. parkeri, R. vitalii and C. thous, are all native to the Atlantic Forest, further studies are needed to evaluate the impact of an exotic canine species - C. lupus familiaris - on the enzootic cycles of R. vitalii and R. parkeri, as well as the possible role of domestic dogs in emergence and re-emergence of R. parkeri-spotted fever in humans and canine rangeliosis, respectively. (AU)

• FAPESP's process: 20/05987-1 - Dichotomic and pictorial taxonomic key for larvae of the genus Amblyomma (Parasitiformes: Ixodidae) that occur in Brazil, using optical and scanning electron microscopy for description and morphological redescription of the larval stage
• Grantee: Thiago Fernandes Martins
• Support Opportunities: Scholarships in Brazil - Young Researchers
• FAPESP's process: 19/03167-0 - Dichotomic and pictorial taxonomic key for larvae of the genus Amblyomma (Parasitiformes: Ixodidae) that occur in Brazil, using optical and scanning electron microscopy for description and morphological redescription of the larval stage
• Grantee: Thiago Fernandes Martins
• Support Opportunities: Research Grants - Young Investigators Grants