Sand Fly Fauna and Prevalence of spp. in a Newly Investigated Area of Northern Italy: Emerging Epidemiological Scenarios?

Since the 1990s, cases of canine leishmaniasis (CanL) due to have risen in northern Italy due to dog translocation and movement as well as for climate-driven sand fly population growth. In this geographical region, for a long time regarded as non-endemic for CanL, is generally transmitted by the sand flies of the genus . Other sand flies, such as , have been less investigated, also because they were only considered as vectors of the nonpathogenic herpetophilic . Our study investigates sand fly species composition and spp. prevalence in hilly areas of northern Italy, in the Bergamo district. Sand flies were sampled with both sticky and light traps. Common wall lizards have been captured in the same areas, for the collection of biological samples: blood, feces, tissues, and gut-associated secretions. Sand flies were identified morphologically (males) and molecularly (females). The collected samples were tested for the presence of spp. via conventional and digital droplet PCR. Our study reports the presence of , , and in the investigated area. We report the first detection of , a species, in northern Italy, in both sand fly vectors (, , and ) and reptile hosts. Additionally, DNA was detected, for the first time, in sand flies and reptiles in the district, spatially overlapping with previously reported local CanL cases. Our study reported the presence of three sand fly species in the Bergamo district, a species (the first record in northern Italy), and the occurrence of . We emphasize the importance of including both sand flies and synanthropic reptiles in leishmaniasis screenings for a better understanding of the epidemiology of the disease.