Detection of Leishmania spp. in Cats: Analysis of Nasal, Oral and Conjunctival Swabs by PCR and HRM.

BACKGROUND AND OBJECTIVES: Feline leishmaniasis (FeL) is caused by several species of parasites of the genus Leishmania. The disease can occur with the presence or absence of clinical signs, similar to those observed in other common infectious diseases. In endemic regions for FeL, the infection has been associated with dermatological lesions. Therefore, considering the search for less invasive and more effective diagnostic techniques, we aimed to investigate the presence of Leishmania spp. in domestic cats through Polymerase Chain Reaction (PCR) and high-resolution melting (HRM) analyses of conjunctival, oral, and nasal epithelial cells, and we detected the presence of anti-Leishmania IgG antibodies from serological techniques of the Immunofluorescent Antibody Test (IFAT) and ELISA. METHODS: The PCR and HRM for detection of Leishmania spp. were performed on 36 samples of epithelial cells from the conjunctiva of male and female cats, collected using sterile swabs. The serological tests IFAT and ELISA were also performed. RESULTS: The prevalence of Leishmania donovani infection was 11.1% (4/36) by PCR assay, and those results were confirmed for Leishmania species using the HRM technique. Twenty-four cats (24/36 = 66.7%) were reactive to the IFAT and twenty-two cats were reactive by the ELISA technique (22/36 = 61.1%). INTERPRETATION AND CONCLUSIONS: The use of conjunctival swabs was shown to be a non-invasive, practical, and easy-to-perform technique, and in addition to the genetic sequencing and HRM, it was able to identify the parasitic DNA of L. donovani in cats. This technique can be used for screening diagnosis in future epidemiological surveys of FeL and can be used as a complement to clinical and/or serological tests, as well as associating the clinical history of the animal, for the diagnostic conclusion.

Diagnóstico de leptospira spp. en bovinos sacrificados en brasil / Diagnostic of leptospira spp. in slaughtered cattle from brazil / Diagnóstico de leptospira spp. em bovinos abatidos no brasil

La leptospirosis es considerada una zoonosis bacteriana de importancia en salud pública. Es común en áreas tropicales, especialmente en países en desarrollo con escasos recursos de salud y saneamiento. Este estudio evaluó la presencia de Leptospira spp. en bovinos sacrificados en un matadero de la región Centro-Oeste de São Paulo, Brasil, así como animales positivos identificados tanto en serología como por análisis molecular. Se investigaron muestras biológicas de sangre, hígado y riñones de 150 bovinos mediante la técnica de Prueba de Aglutinación Microscópica (MAT) y Reacción en Cadena de la Polimerasa convencional (cPCR). Los resultados serológicos mostraron que de los 150 animales, 71 (47,3%) fueron reactivos. Los resultados moleculares mostraron la presencia de Leptospira spp. en riñones de 21 (14%) animales, en hígado de cinco (3,3%) animales, en hígado y riñones en dos animales (1,3%) y en sangre, en un (0,7%) animal. Estos resultados indican una alerta sobre la salud de los bovinos de carne debido a la posibilidad de que estos animales sean fuente de infección y la importancia de la característica ocupacional de esta enfermedad. También se verificó la importancia de complementar las técnicas serológicas y moleculares.  

Leptospirosis is considered a bacterial zoonosis of public health importance. It is common in tropical areas, especially in developing countries with scarce health and sanitation resources. This study evaluated the presence of Leptospira spp. in slaughtered bovine in a slaughterhouse in the Midwest region of São Paulo, Brazil, as well as identified positive animals both in serology and by molecular analysis. Biological samples of blood, liver and kidneys from 150 cattle were investigated by the technique of Microscopic Agglutination Test (MAT) and conventional Polymerase Chain Reaction (cPCR). The serological results showed that of the 150 animals, 71 (47.3%) were reactive. The molecular results showed the presence of Leptospira spp. in kidneys of 21 (14%) animals, in liver of five (3.3%) animals, in liver and kidneys in two animals (1.3%) and in blood, in one (0.7%) animal. These results indicate a warning about the health of beef cattle due to the possibility of these animals being the source of infection and the importance of the occupational characteristic of this disease. It was also verified the importance of complementing serological and molecular techniques.

A leptospirose é considerada uma zoonose bacteriana de importância para a saúde pública. É comum em áreas tropicais, especialmente em países em desenvolvimento com escassos recursos de saúde e saneamento. Este estudo avaliou a presença de Leptospira spp. em bovinos abatidos em frigorífico da região Centro-Oeste de São Paulo, Brasil, e identificou animais positivos tanto por sorologia quanto em análise molecular. Amostras biológicas de sangue, fígado e rins de 150 bovinos foram investigadas pela técnica de Teste de Aglutinação Microscópica (MAT) e Reação em Cadeia da Polimerase convencional (cPCR). Os resultados sorológicos mostraram que dos 150 animais, 71 (47,3%) foram reativos. Os resultados moleculares mostraram a presença de Leptospira spp. nos rins de 21 animais (14%), no fígado de 5 animais (3,3%), no fígado e rins em 2 animais (1,3%) e no sangue em 1 animal (0,7%). Esses resultados indicam um alerta sobre a saúde dos bovinos de corte devido à possibilidade desses animais serem fonte de infecção e a importância da característica ocupacional desta doença. Verificou-se também a importância de complementar as técnicas sorológicas e moleculares.

First isolation of Leishmania infantum by blood culture in bovines from endemic area for canine visceral leishmaniasis.

Leishmaniasis is considered a parasitic disease that still causes serious consequences for mankind, because it presents a high mortality rate worldwide. Considered multi-hosts, the parasites of the genus Leishmania are able of infecting a wide variety of animal species. The dog was considered the main source of infection of visceral leishmaniasis (VL), in the urban area. However, the role of other animal species in the epidemiological cycle of the disease, such as cattle, remains unclear. Therefore, the aim of the present study was to evaluate the occurrence of Leishmania spp. in 100 bovines (Bos taurus) from an area endemic for canine VL, using blood culture and molecular analysis. By the sequencing analysis, one sample showed 100% similarity with Leishmania infantum. The results provide the first case of L. infantum isolation in one bovine from the periurban areas of Bauru, state of São Paulo, Brazil.