Detection of Leishmania infantum DNA in captive wild mammals from an urban zoo in a visceral leishmaniasis–endemic area of Brazil

Abstract

Background Visceral leishmaniasis (VL) is a complex zoonotic disease transmitted to humans through the bites of Leishmania-infected phlebotomine sand flies (Diptera:Psychodidae:Phlebotominae). Its transmission dynamics are shaped by environmental, ecological, and anthropogenic factors. Rapid urbanization, landscape modification, and the rising incidence of human and canine VL in endemic cities raise concerns about parasite circulation at the human-wildlife interface, including within captive animal populations housed in urban zoological institutions. Methodology/principal findings This study was conducted at the Belo Horizonte Zoo (Minas Gerais, Brazil), located in one of city's most VL-affected districts. We collected 31 skin biopsies and 40 blood samples from 13 captive mammal species—11 primates (Alouatta guariba, Aotus nigriceps, Ateles marginatus, Gorilla gorilla, Lagothrix lagotricha, Leontopithecus rosalia, Leontopithecus chrysopygus, Pan troglodytes, Pithecia irrorata, Saguinus imperator, Sapajus xanthosternos) and 2 carnivores (Chrysocyon brachyurus and Leopardus colocolo). Samples were screened using a complementary molecular diagnostic panel: Leishmania nested PCR (LnPCR), real time PCR (qPCR), and K26 loop-mediated isothermal amplification (K26-LAMP). Leishmania DNA was detected in the blood of a clinically healthy adult maned wolf (Chrysocyon brachyurus). Sequencing and phylogenetic analysis of the LnPCR amplicon confirmed the presence of Leishmania infantum. The animal was housed in an enclosure with documented high densities of Lutzomyia longipalpis, the primary VL vector in the region. Conclusions/significance The detection of Leishmania infantum DNA in a zoo-housed wild canid within an VL-endemic urban area highlights the potential exposure of captive wildlife to local transmission cycles. Although infectivity and reservoir competence were not assessed, these findings underscore the importance of integrating minimally invasive molecular surveillance with entomological monitoring in zoological institutions. Such an integrated approach can strengthen One Health surveillance frameworks by enabling early detection of parasite circulation, informing risk-based management strategies, and supporting VL prevention efforts in complex urban environments.