Molecular and serological detection of Leishmania infantum , Toxoplasma gondii , and Leptospira spp. in free-ranging capybaras ( Hydrochoerus hydrochaeris ) from the Atlantic Forest

Due to the ecological changes and imbalance in their natural habitat, capybaras have been found in both urban and rural areas in Brazil, which may favor the transmission of pathogens with zoonotic potential. Furthermore, in the northeastern region, there are no studies about the pathogens of free-ranging capybaras. The objective of this study was to demonstrate the role of capybaras as bioindicators of the presence of zoonotic pathogens and Neospora caninum in three Atlantic Forest remnants. For this, blood samples of 21 free-ranging capybaras were collected for the molecular detection of Leishmania infantum and serological detection of anti-Toxoplasma gondii, anti-N. caninum, and anti-Leptospira spp. antibodies. The molecular prevalence of L. infantum was 38.09%, while serological prevalence of T. gondii was 33.3%. The anti-Leptospira interrogans serovar Icterohaemorrhagiae (47.6%) and anti-L. borgpetersenii serovar Tarassovi antibodies (4.8%) were also detected. These pathogens were detected in animals in all three study areas, but no anti-N. caninum antibodies were detected in any of the animals studied. The results obtained show the role of free-ranging capybaras as bioindicators of zoonotic pathogens, which points to the need for surveillance programs to watch for the emergence of Visceral Leishmaniasis, Toxoplasmosis, and Leptospirosis in human and animal populations in the studied areas. The information from this study may support public policies for the conservation of capybaras and the ecosystems where these animals live, as well as for epidemiology and control of diseases within the One Health approach.