Leishmania infantum infection rate in dogs housed in open-admission shelters is higher than of domiciled dogs in an endemic area of canine visceral leishmaniasis. Epidemiological implications

•Among 627 dogs housed in open-admission shelters, 211 (33.6%) were seropositive for canine visceral leishmaniasis.•PCR-RFLP of 118 seropositive animals confirmed 78 (66.1%) infected with Leishmania infantum, 7 (5.9%) with L. amazonensis and 1 (0.8%) with both.•L. amazonensis DNA was detected in skin samples of six single-infected animals.•Dog shelters may be foci of Leishmania for adjoining dog and human populations.•Public authorities should control collective shelters to safeguard animal welfare.