Roe deer (Capreolus capreolus) are a novel potential reservoir for human visceral leishmaniasis in the Emilia-Romagna region of northeastern Italy

•Leishmania infantum is the only Leishmania species circulating in Italy.•In the Emilia-Romagna region, humans and dogs are infected by two distinct L. infantum strains.•For the first known time L. infantum infection was recorded in ruminants (roe deer).•Over 90% of L. infantum infections in deer are associated with the “human” strain.•This result suggests that these animals are a novel reservoir for human visceral leishmaniasis.