Serological, molecular, and microscopic detection of Leishmania in cats (Felis catus) in Belo Horizonte, Minas Gerais State, Brazil

Abstract

The role of cats in the epidemiological cycle of leishmaniasis remains unclear. To better understand the occurrence of leishmaniasis in cats, we studied the frequency of Leishmania in serum samples of 100 cats living in an endemic region for canine and human leishmaniasis by serological, parasitological, and molecular methods. Of the 100 cats, 54 were seropositive for Leishmania antibodies by immunofluorescence antibody test. None of the bone marrow aspirates collected from these cats tested positive for the parasite in culture or upon polymerase chain reaction (PCR) analysis. Biopsy samples of the ears also tested negative for Leishmania upon PCR analysis. These findings may indicate that the region is endemic for canine leishmaniasis and cats are infected by Leishmania; or that cross-reaction with antibodies against other parasites increases the frequency of seropositivity; or that cats respond to Leishmania infection by producing antibodies when few or no parasites are present in bone marrow and tissue samples. Overall, our results suggest that cats can be infected by Leishmania ; however, we failed to demonstrate feline parasitosis. These findings highlight the need to study leishmaniasis in cats, since sandflies feed on cats, these animals may act as a reservoir for the parasite.

Serological and molecular investigation of Leishmania spp. infection in cats from an area endemic for canine and human leishmaniasis in Northeast Brazil

“…Similar results were observed by other authors, i.e., seropositive cats testing negative on PCR (BRAGA et al, 2014;CHATZIS et al, 2014;NOÉ et al, 2015;MONTOYA et al, 2018;COURA et al, 2018). This finding could be explained by the capability of the protozoan to compartmentalize in determined lymphoid organs such as bone marrow, lymph nodes, and spleen, by the absence of parasitemia at the moment of the blood collection, or because of a parasite burden lower than that of the detection limit of the test used (CHATZIS et al, 2014;COURA et al, 2018). Another hypothesis for the presence of seropositive animals with negative PCR result could be related to the possibility of cross-reactions with antibodies against other parasites, especially other species of Leishmania and Trypanosoma (ZANETTE et al, 2014;SILVEIRA et al, 2015;SOARES et al, 2016).…”

“…using PCR from blood samples did not give positive results for any of the animals. Similar results were observed by other authors, i.e., seropositive cats testing negative on PCR (BRAGA et al, 2014;CHATZIS et al, 2014;NOÉ et al, 2015;MONTOYA et al, 2018;COURA et al, 2018). This finding could be explained by the capability of the protozoan to compartmentalize in determined lymphoid organs such as bone marrow, lymph nodes, and spleen, by the absence of parasitemia at the moment of the blood collection, or because of a parasite burden lower than that of the detection limit of the test used (CHATZIS et al, 2014;COURA et al, 2018).…”

“…The FeL seropositivity here was higher than that observed in Recife and Teresina, where 3.9% and 4% of the cats were found be seropositive for FeL using ELISA (SILVA et al, 2014;MENDONÇA et al, 2017). Sero-epidemiological investigations in other regions of the country found frequencies varying from 0.5% to 54%, using IFAT and the same cut-off value adopted here (1:40) (VIDES et al, 2011;CARDIA et al, 2013;BRAGA et al, 2014;SOUSA et al, 2014;OLIVEIRA et al, 2015;GODOI et al, 2016;COURA et al, 2018;MATOS et al, 2018). In canine leishmaniasis, high serological titers (four times the established cut-off value) with clinical signs compatible with leishmaniasis are diagnostic for the disease (SOLANO-GALLEGO et al, 2011).…”

“…In Brazil, studies on FeL using serological, parasitological, and molecular methods revealed that infection frequencies varied from 0% to 54% (BRESCIANI et al, 2010;VIDES et al, 2011;CARDIA et al, 2013;BRAGA et al, 2014;SILVA et al, 2014;SOUSA et al, 2014;OLIVEIRA et al, 2015;GODOI et al, 2016;MENDONÇA et al, 2017;COURA et al, 2018;MATOS et al, 2018). Only a small fraction of these studies was performed in the Northeast region that was home to 82.5% of all reported cases of human leishmaniasis in Brazil between 1980 and 2005, making this region an area of epidemiological relevance for this disease in Brazil (MAIA-ELKHOURY et al, 2008;SILVA et al, 2014;MENDONÇA et al, 2017).…”

Leishmaniasis in cat shelters: A serological, molecular and entomological study

“…that have been described in epidemiological surveys conducted in Brazil and São Paulo state. Illustrative map based on twenty-four articles published in peer-reviewed scientific journals between 1940 and 2019, and the results from the present study (Benassi et al, 2017;Bresciani, Serrano, Matos, Savani, & D'Auria, 2010;Cardia, Camossi, Neto, Langoni, & Bresciani, 2013;Coelho et al, 2010;Coelho, Richini-Pereira, Langoni, & Bresciani, 2011;Costa et al, 2010;Coura et al, 2018;Figueiredo et al, 2009;Marcondes et al, 2018;Mello, 1940;Mendonça et al, 2017;Metzdorf et al, 2017;Oliveira et al, 2015;Rocha et al, 2019;Savani et al, 2004;Schubach et al, 2004;Sherlock, 1996;Silva, Cândido, Pita-Pereira, Brazil, & Carreira, 2008;Silveira-Neto et al, 2011;Simões-Mattos et al, 2001;Sobrinho et al, 2012;Souza et al, 2005;Souza, Nunes, Borralho, & Ishikawa, 2009;Vides et al, 2011). Map made with the QGIS 2.18 "Las Palmas" software (QGIS Development Team, 2016) using free access datasets from Instituto Brasileiro de Geografia e Estatística [IBGE] (2018) [Colour figure can be viewed at wileyonlinelibrary.com] species present in the city.…”