Natural infection of the wild canid, Cerdocyon thous, with the piroplasmid Rangelia vitalii in Brazil

Abstract

Canine rangeliosis, caused by the piroplasmid protozoon Rangelia vitalii, is currently recognized as a reemerging disease that affects domestic dogs in Brazil. In the present study, piroplasmid infection was searched in wild canids (20 Cerdocyon thous and 4 Lycalopex gymnocercus) in Brazil. Molecular analysis, based on PCR and DNA sequencing of a portion of the 18S rRNA gene, revealed that 30% (6/20) C. thous were infected by R. vitalii. Blood and bone marrow samples from one of the R. vitalii-infected C. thous were inoculated into a domestic dog, which developed clinical rangeliosis that was confirmed by molecular tests. However, the C. thous donor showed no clinical, hematological or biochemical alterations, even though its R. vitalii infection status was confirmed for at least 80 days. These observations suggest that R. vitalii is not as highly pathogenic for C. thous as it is for domestic dogs. Phylogenetic analysis inferred by the 18S rRNA gene placed R. vitalii embedded in the clade 'Babesia sensu stricto', consisting of a number of species that represent truly the genus Babesia. It is proposed that the species R. vitalii should be transferred to the genus Babesia. The present study expands our knowledge on the natural history of R. vitalii, suggesting that it might have a natural cycle involving the wild canid C. thous. Further studies are needed to confirm that C. thous is a natural reservoir of R. vitalii in Brazil.

Clinical and hematological evaluation of Rangelia vitalii-naturally infected dogs in southeastern Brazil

“…It is easier to view the parasite during fever peaks in blood smears (PESTANA, 1910b;SILVA et al, 2011). It has been shown that the tick Amblyomma aureolatum is the vector responsible for its transmission (SOARES et al, 2014). This tick species also infects wild animals, which are thought to act as reservoirs for R. vitalii.…”

“…This tick species also infects wild animals, which are thought to act as reservoirs for R. vitalii. Molecular studies have detected R. vitalii in the blood of Cerdocyon thous and Lycalopex gymnocercus (SOARES et al, 2014;QUADROS et al, 2015). Rangelia vitalii-infected dogs are found in rural and urban fringe areas, especially in areas close to forest and wilderness (BRAGA, 1935;LORETTI & BARROS, 2004).…”

Rangeliosis: histopathological analysis, hematology and molecular detection of canine Rangelia vitalii in Rio Grande do Sul, Brazil

“…In Brazil, rangeliosis is diagnosed in wild canids using PCR (SOARES et al, 2014) and macroscopic and histological analyses (FREDO et al, 2015). The disease has also been described in other countries of South America, such as Argentina (EIRAS et al, 2014) and Uruguay (SOARES et al, 2015).…”

“…Recently, two real-time polymerase chain reaction (qPCR) assays have been developed to detect and quantify R. vitalii in the blood of dogs. One uses the 18s RNA gene fragment with SYBR ® Green (PAIM et al, 2016), and the other uses a TaqMan probe (SOARES et al, 2014).…”

Molecular Detection of Rangelia Vitalii in a Dog From the Curitiba Metropolitan Region, Parana State, Southern Brazil

“…Several emerging vector-borne pathogens have also been described and may represent a challenge in diagnosis, since clinical signs may be misinterpret (DantasTorres and Otranto, 2016). The piroplasm Rangelia vitalii is etiological agent of canine rangeliosis, and have been described infecting domestic and wild canids in South America (Eiras et al, 2014;Quadros et al, 2015;Soares et al, 2015Soares et al, , 2014, mainly in the South and Southeastern Brazilian states (Gottlieb et al, 2016;Lemos et al, 2017;Malheiros et al, 2016;Quadros et al, 2015;Silveira et al, 2016;Soares et al, 2014Soares et al, , 2011. Canine rangeliosis may cause a variety of clinical signs, such as apathy, intermittent fever, ear's margin bleeding and anemia (França et al, 2014), with an average lethality rate of 33,3% (Soares, 2014).…”