Leishmania spp. in Squamata reptiles from the Mediterranean basin

Leishmania tarentolae is a nonpathogenic trypanosomatid species isolated from geckoes in the Mediterranean basin. In Italy, L. tarentolae and Leishmania infantum occur in sympatry in areas where canine leishmaniosis (CanL) is endemic. Here, we investigated the prevalence and distribution of L. tarentolae in reptilian hosts and the presence of L. infantum in the same animals in southern Italy. From April 2020 to April 2021, lizards and snakes were captured in urban, peri-urban sites, natural parks, and dog shelters. Blood was individually sampled and assessed for the presence of Leishmania spp. by cytology and/or molecular biology. Captured lizards were euthanized and their tissues/organs were tested by duplex real-time-PCR for the detection of L. infantum and L. tarentolae and the positive ones were amplified by conventional PCR to confirm the species identification by sequencing. Samples were also screened by real-time PCR for L. infantum kDNA minicircle. Of the 259 collected Squamata reptiles, 34 (13.1%) specimens scored positive for Leishmania spp., with a prevalence of 10% for L. tarentolae (n = 26) and of 3.1% for L. infantum (n = 8). Positive lizards were mostly Podarcis siculus (n = 26) from dog shelters, with six specimens positive for L. infantum. In addition, L. tarentolae was detected in one Podarcis filfolensis lizard, and in five T. mauritanica geckos (with one gecko and P. filfolensis lizard showing amastigote-like forms in thrombocytes), whereas L. infantum was detected in one T. mauritanica, and one Hemidactylus turcicus. Data herein reported demostrate that saurian reptiles living in CanL endemic areas of the Mediterranean basin may be exposed to both L. tarentolae and L. infantum indicating a sympatric circulation of these species in different vertebrate hosts. Moreover, this study represents the first molecular evidence of L. infantum infection in European reptiles.