Ocorrência de infecção por leishmania infantum em felinos domésticos de municípios endêmicos para leishmaniose canina no estado da Bahia

Abstract

This study investigated the occurrence of Leishmania infantum infection in cats and dogs cohabiting in shelters or households located in different municipalities endemic for canine leishmaniasis (CanL) in the state of Bahia, Brazil. The study included 97 cats and 154 dogs. These animals were evaluated through physical examination and, when feasible, clinical pathology, as well as serological testing for the detection of anti Leishmania antibodies. Bone marrow samples were collected for cytology and analyzed via PCR for DNA detection and parasite identification. Infection by L. infantum was confirmed by PCR in 21.6% (21/97) of the cats analyzed. In this study, cats whose cytological exams showed amastigote forms of Leishmania in bone marrow or other tissue samples were classified as having active infection. Among the 21 cats evaluated, five (23.8%) showed evidence of active infection. An in-house ELISA test using the rk39 antigen was standardized for the detection of anti-Leishmania antibodies in cats, and the results were compared with those from the Dual Path Platform rapid test (TR-DPP®, Biomanguinhos). ELISA positivity was observed in 7.4% (6/81), and TR-DPP® positivity in 4.9% (4/81) of the cats. Among dogs tested by PCR, 29.5% (39/132) were positive for L. infantum DNA. The seropositivity rate in dogs, based on TR-DPP® and/or ELISA-EIE® (Biomanguinhos) tests, was 21.5% (31/144). Most infected cats exhibited at least one clinical sign of feline leishmaniasis (FeL), with skin lesions being the most frequent. A significant association was found between infection and ocular alterations and pale mucous membranes (p = 0.0109; CI = 1.291 to 15.23). This is the first report of L. infantum infection in cats in the municipalities of Salvador, Lauro de Freitas, Itaberaba, and Vera Cruz. The findings indicate that cats exposed to L. infantum infection in areas endemic for CanL may develop active infection and clinical disease—FeL. These results highlight the importance of including this species in clinical and epidemiological studies to better characterize the factors related to the role of cats in the transmission cycle and the development of FeL caused by L. infantum in Brazil. Well-founded studies may contribute to knowledge and, consequently, to the development and implementation of coherent surveillance and control strategies for zoonotic leishmaniasis in endemic areas.