Mixed infection of Leishmania (Leishmania) infantum and Leishmania (Viannia) braziliensis in a mare (Equus ferus caballus) from Minas Gerais State, Southeastern Brazil.

Equine leishmaniasis is a widespread disease in Brazil, mainly caused by Leishmania (Viannia) braziliensis, with occasional cases involving Leishmania (Leishmania) infantum. This study reports a mixed infection in a 6-year-old mare from rural Itabirito, Minas Gerais, Brazil. The mare exhibited nodular cutaneous lesions on all limbs but had no other health issues. Skin and bone marrow samples were collected and analyzed using parasitological and molecular methods targeting the hsp70 gene and ITS1 region. Both L. (V.) braziliensis and L. (L.) infantum were identified, confirming a mixed infection. Notably, this is the first confirmed isolation of L. (V.) braziliensis from equine cutaneous lesions. These findings highlight the importance of recognizing equids as potential reservoirs in the transmission of leishmaniasis, which has implications for disease control and epidemiological surveillance.