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.

Flies (Insecta, Diptera) collected in the environment of dairy farms as carriers of Rotavirus A and betacoronavirus.

AIMS: We aimed to investigate the prevalence of rotavirus and coronavirus in dipterans that commonly inhabit the environment of dairy farms. METHODS AND RESULTS: We collected 217 insect specimens from nine dairy farms, which were examined through hemi-nested RT-PCR followed by Sanger sequencing in search of VP1 and N genes for rotavirus and bovine coronavirus-BCoV, respectively. With a predominance of Muscidae (152/217 = 70%) 11 families of Diptera were identified. Rotavirus A (RVA) and betacoronavirus (BCoV) were detected in 14.7% (32/217) and 4.6% (10/217) of the dipterans, respectively. Sequencing of the amplicons was possible for 11.5% (25/217) of RVA and 0.5% (1/217) of BCoV, confirming the presence of these pathogens. CONCLUSIONS: Our findings highlight the role of dipterans as carriers of RVA and BCoV of great relevance for public and animal health.

Commercially acquired açaí pulps contamination by Trypanosoma cruzi.

The etiological agent of Chagas disease is the protozoan Trypanosoma cruzi. According to the World Health Organization, about seven to eight million people are infected with T. cruzi worldwide. The main routes of transmission are vectorial and oral, which has assumed great epidemiological importance, since there is no legislation that requires the pasteurization of açaí pulp. The present work aimed to look T. cruzi in 35 samples of açaí ice cream sold at different points of sale, covering 11 different cities in São Paulo State. Thus, the parasitological technique of forced sieving and the molecular test of Polymerase Chain Reaction were performed. For PCR analysis were used the 121/122 primer that amplifies the kinetoplast of the T. cruzi DNA (kDNA). By the forced sieving technique, the açaí pulp aliquots were analyzed under different storage temperatures and in different periods. One positive sample (2.86%) were observed at six hours at room temperature, but without motility and negative to the PCR technique. Two other açaí samples (5.71%) were positive by PCR, but negative by forced sieving. The results indicate the need for quality control and good manufacturing practices for the safe consumption of açaí-derived products.

TRYPANOSOMA spp. in captive primates in a brazilian zoo

Captive animals, despite the constant care provided, are susceptible to infections from different sources. We herein report the natural trypanosome infection of 11 (28.2% positive) out of 39 non-human primates from 13 different species, in a Brazilian zoological park. Immunofluorescent antibody test (IFAT) and conventional polymerase chain reaction (cPCR) ruled out Trypanosoma cruzi, the etiological agent of Chagas disease. However, sequencing performed with positive samples employing hsp70 primers revealed similarities from 86% to 88% to diverse trypanosomes, including T. cruzi, Trypanosoma grayi, Trypanosoma lewisi, Trypanosoma rangeli and Trypanosoma vivax. We believe that the low similarity values obtained by sequencing reflect the difficulties in the molecular identification of trypanosomes, which share a large portion of their genetic material; this similarity may also preclude the diagnosis of co-infection by more than one trypanosome species. Thus, our study demonstrates the presence of diverse trypanosomes in primates, which are susceptible to infection by these parasites. Mechanical devices such as windows and bed nets, etc., are required to avoid vector insects in these environments, in addition to preventive quarantining of animals recently introduced into zoos. Therefore, investigation of the parasites in both the animals already residing in the zoo and those being introduced is of paramount importance, although no easy task.

Extracellular vesicles in infectious diseases caused by protozoan parasites in buffaloes.

BACKGROUND: Extracellular vesicles (EVs) are small membrane-bound vesicles of growing interest in vetetinary parasitology. The aim of the present report was to provide the first isolation, quantification and protein characterization of EVs from buffalo (Bubalus bubalis) sera infected with Theileria spp. METHODS: Infected animals were identified through optical microscopy and PCR. EVs were isolated from buffalo sera by size-exclusion chromatography and characterized using western blotting analysis, nanoparticle tracking analysis and transmission electron microscopy. Subsequently, the proteins from isolated vesicles were characterized by mass spectrometry. RESULTS: EVs from buffalo sera have shown sizes in the 124-140 nm range and 306 proteins were characterized. The protein-protein interaction analysis has evidenced biological processes and molecular function associated with signal transduction, binding, regulation of metabolic processes, transport, catalytic activity and response to acute stress. Five proteins have been shown to be differentially expressed between the control group and that infected with Theileria spp., all acting in the oxidative stress pathway. CONCLUSIONS: EVs from buffaloes infected with Theileria spp. were successfully isolated and characterized. This is an advance in the knowledge of host-parasite relationship that contributes to the understanding of host immune response and theileriosis evasion mechanisms. These findings may pave the way for searching new EVs candidate-markers for a better production of safe biological products derived from buffaloes.

Should we be concerned about COVID-19 with nonhuman primates?

The coronavirus disease 2019 pandemic has radically changed the human activities worldwide. Although we are still learning about the disease, it is necessary that primatologists, veterinarians, and all that are living with nonhuman primates (NHP) be concerned about the probable health impacts as these animals face this new pandemic. We want to increase discussion with the scientific community that is directly involved with these animals, because preliminary studies report that NHP may become infected and develop symptoms similar to those in human beings.

Diversity of Blastocystis subtypes in wild mammals from a zoo and two conservation units in southeastern Brazil.

The enteric protist Blastocystis is one of the most commonly parasite reported in humans and a variety of animal hosts worldwide. Regarding genetic diversity, at least 17 subtypes (STs) have been identified in mammals and birds, with eight of them (ST1-8) infecting both humans and animals. Recently, isolates from wild mammalian species have been genetically characterized, however data is still scarce, mainly in Latin America. Here, we aimed to verify the occurrence and genetic diversity of Blastocystis in captive wild mammals kept in one zoo and in two units of protection and conservation in southeastern Brazil. A total of 78 fecal samples (14 pooled and 64 individual samples) were recovered from 102 wild mammals of 35 species included in the following orders: Primates, Carnivora, Artiodactyla, Pilosa, Rodentia and Marsupialia. Zoo and units staff were invited to participated but only 16 fecal samples could be screened. Based on the sequence analyses of SSUrDNA gene, out of 29 PCR products from animal samples, 51.7% (15/29) were successfully sequenced and five Blastocystis subtypes were identified as follows: ST1 (2/15; 13.3%), ST2 (2/15; 13.3%), ST3 (4/15; 26.6%), ST5 (2/15; 13.3%) and ST8 (5/14; 33.3%). Only four isolates from humans were sequenced and identified as ST1 (2 isolates), ST2 and ST3. It was observed that Blastocystis infecting non-human primates belong to ST1 and ST2 and mainly to ST3 and ST8, artiodactyls ST5, carnivores ST1 and ST5 and rodents ST1. In addition, this present study reports some interesting findings: (1) 63% (12/19) of Blastocystis isolates from animals and employees belonged to the potentially zoonotic subtypes ST1-ST3; (2) most of these isolates displayed high identity with publicly available DNA sequences from non-human primates and humans, including primate handlers; (3) Blastocystis ST5 was found infecting the northern tiger cat, a native South American felid and one of the species facing a high risk of extinction in Brazil.

Extracellular vesicles in infectious diseases caused by protozoan parasites in buffaloes

Extracellular vesicles (EVs) are small membrane-bound vesicles of growing interest in vetetinary parasitology. The aim of the present report was to provide the first isolation, quantification and protein characterization of EVs from buffalo (Bubalus bubalis) sera infected with Theileria spp. Methods: Infected animals were identified through optical microscopy and PCR. EVs were isolated from buffalo sera by size-exclusion chromatography and characterized using western blotting analysis, nanoparticle tracking analysis and transmission electron microscopy. Subsequently, the proteins from isolated vesicles were characterized by mass spectrometry. Results: EVs from buffalo sera have shown sizes in the 124-140 nm range and 306 proteins were characterized. The protein-protein interaction analysis has evidenced biological processes and molecular function associated with signal transduction, binding, regulation of metabolic processes, transport, catalytic activity and response to acute stress. Five proteins have been shown to be differentially expressed between the control group and that infected with Theileria spp., all acting in the oxidative stress pathway. Conclusions: EVs from buffaloes infected with Theileria spp. were successfully isolated and characterized. This is an advance in the knowledge of host-parasite relationship that contributes to the understanding of host immune response and theileriosis evasion mechanisms. These findings may pave the way for searching new EVs candidate-markers for a better production of safe biological products derived from buffaloes.(AU)

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.

Anti-leptospirosis agglutinins in Brazilian capybaras (hydrochoerus hydrochaeris).

BACKGROUND: The interest in commercial use of wild animals is increasing, especially regarding raising of capybaras. Although this wild species is potentially lucrative for the production of meat, oil and leather, it is suggested as a probable reservoir of leptospires. METHODS: Due to the economic importance of this species and the lack of studies concerning leptospirosis, the presence of anti-leptospirosis agglutinins was assayed in 55 serum samples of capybaras (Hydrochoerus hydrochaeris) from commercial and experimental breeding flocks located in São Paulo state, Paraná state, and Rio Grande do Sul state, Brazil. Samples were obtained through cephalic or femoral venipunction (5 to 10 mL). Microscopic agglutination test was used according to the Brazilian Health Ministry considering as cut-off titer of 100. RESULTS: Out of the 55 samples analyzed, 23 (41.82 %) tested positive. The most prevalent serovar was Icterohaemorrhagiae (56.52 %) in 13 samples, followed by Copenhageni in nine samples (39.13 %), Pomona in four samples (17.39 %), Djasiman and Castellonis in three samples each (13.04 %), Grippotyphosa, Hardjo, Canicola, and Cynopteri in two samples each (8.7 %), and Andamana and Bratislava in one sample each (4.34 %). CONCLUSIONS: These results suggest the evidence of exposure to Leptospira spp. and the need of new studies to evaluate a higher number of capybaras from different regions to better understand the importance of leptospirosis infection in these animals and verify the zoonotic role of this species as a possible source of infection to humans and other animals.

Occurrence of antibodies to Toxoplasma gondii in opossums caught in urban areas of Bauru, state of São Paulo, Brazil / Ocorrência de anticorpos para Toxoplasma gondii em gambás capturados na área urbana de Bauru, Estado de São Paulo, Brasil

Toxoplasmosis is one of the most common zoonoses worldwide. It was initially described in rodents and rabbits. There are few data on the morbidity and mortality of this disease among Brazilian marsupial fauna, such as opossums. These animals are of great importance regarding the epidemiology of this disease, given that they are prey for felids and other carnivores. With the aim of ascertaining the serological response to Toxoplasma gondii among marsupials (Didelphis spp.), 38 animals that had been caught in 14 districts of the urban area of the municipality of Bauru, state of São Paulo, were evaluated. The modified agglutination test (MAT) showed that 26.3% (10/38) of the samples analyzed were seropositive. It can be suggested that the opossums' behavior and persistent proximity to human housing results in contact with cats and T. gondii infection, based on the frequency found in this study. This was the first study on the seroprevalence of T. gondii in opossums caught in the urban area of the municipality of Bauru, SP, and it highlights the need for environmental and health authorities of the municipality to monitor this zoonosis.(AU)

A toxoplasmose é uma das zoonoses mais comuns no mundo, tendo sido descrita inicialmente em roedores e em coelhos. Todavia, poucos são os dados sobre morbidade e mortalidade da toxoplasmose nos marsupiais da fauna brasileira, como os gambás, sendo de grande importância na epidemiologia da doença, como presas para felídeos e outros carnívoros. Com o objetivo de verificar a resposta sorológica para Toxoplasma gondii em marsupiais (Didelphis spp.), foram avaliados 38 animais capturados em 14 regiões da área urbana do município de Bauru-SP. Foi encontrada uma frequência, de acordo com o teste de aglutinação modificada (MAT), de 26,3% (10/38) nas amostras analisadas. Pode-se sugerir que o comportamento dos gambás e sua permanência próxima a habitações humanas resultam em contato com gatos e infecção por T. gondii, tendo em vista a frequência encontrada neste estudo. Este é o primeiro estudo de soroprevalência de T. gondii em gambás capturados na área urbana do município de Bauru-SP, alertando-se para a necessidade do monitoramento desta zoonose pelas autoridades de vigilância ambiental e sanitária do município.(AU)

Anti-leptospirosis agglutinins in Brazilian capybaras (hydrochoerus hydrochaeris)

The interest in commercial use of wild animals is increasing, especially regarding raising of capybaras. Although this wild species is potentially lucrative for the production of meat, oil and leather, it is suggested as a probable reservoir of leptospires. Methods Due to the economic importance of this species and the lack of studies concerning leptospirosis, the presence of anti-leptospirosis agglutinins was assayed in 55 serum samples of capybaras (Hydrochoerus hydrochaeris) from commercial and experimental breeding flocks located in São Paulo state, Paraná state, and Rio Grande do Sul state, Brazil. Samples were obtained through cephalic or femoral venipunction (5 to 10 mL). Microscopic agglutination test was used according to the Brazilian Health Ministry considering as cut-off titer of 100. Results Out of the 55 samples analyzed, 23 (41.82 %) tested positive. The most prevalent serovar was Icterohaemorrhagiae (56.52 %) in 13 samples, followed by Copenhageni in nine samples (39.13 %), Pomona in four samples (17.39 %), Djasiman and Castellonis in three samples each (13.04 %), Grippotyphosa, Hardjo, Canicola, and Cynopteri in two samples each (8.7 %), and Andamana and Bratislava in one sample each (4.34 %). Conclusions These results suggest the evidence of exposure toLeptospira spp. and the need of new studies to evaluate a higher number of capybaras from different regions to better understand the importance of leptospirosis infection in these animals and verify the zoonotic role of this species as a possible source of infection to humans and other animals.

Anti-leptospirosis agglutinins in Brazilian capybaras (hydrochoerus hydrochaeris)

Abstract Background The interest in commercial use of wild animals is increasing, especially regarding raising of capybaras. Although this wild species is potentially lucrative for the production of meat, oil and leather, it is suggested as a probable reservoir of leptospires. Methods Due to the economic importance of this species and the lack of studies concerning leptospirosis, the presence of anti-leptospirosis agglutinins was assayed in 55 serum samples of capybaras (Hydrochoerus hydrochaeris) from commercial and experimental breeding flocks located in São Paulo state, Paraná state, and Rio Grande do Sul state, Brazil. Samples were obtained through cephalic or femoral venipunction (5 to 10 mL). Microscopic agglutination test was used according to the Brazilian Health Ministry considering as cut-off titer of 100. Results Out of the 55 samples analyzed, 23 (41.82 %) tested positive. The most prevalent serovar was Icterohaemorrhagiae (56.52 %) in 13 samples, followed by Copenhageni in nine samples (39.13 %), Pomona in four samples (17.39 %), Djasiman and Castellonis in three samples each (13.04 %), Grippotyphosa, Hardjo, Canicola, and Cynopteri in two samples each (8.7 %), and Andamana and Bratislava in one sample each (4.34 %). Conclusions These results suggest the evidence of exposure toLeptospira spp. and the need of new studies to evaluate a higher number of capybaras from different regions to better understand the importance of leptospirosis infection in these animals and verify the zoonotic role of this species as a possible source of infection to humans and other animals.

Evaluation of canine and feline leishmaniasis by the association of blood culture, immunofluorescent antibody test and polymerase chain reaction.

BACKGROUND: This study aimed to evaluate the occurrence of Leishmania spp. in dogs and cats from Botucatu, São Paulo state, and Campo Grande, Mato Grosso do Sul state, Brazil, by the association of three diagnostic tests: blood culture in liver infusion tryptose medium, immunofluorescent antibody test and polymerase chain reaction. Fifty blood samples of dogs and cats from the Center for Zoonosis Control in Campo Grande, an area endemic for canine visceral leishmaniasis, were collected randomly, as well as canine and feline blood samples from the Municipal Kennel and Animal Protection Association in Botucatu, currently considered a transmission-free, non-endemic area. RESULTS: Of the 50 dog blood cultures from Botucatu, three (6%) were positive and of the 50 cats, two (4%) were positive. In Campo Grande, 29 dog blood cultures (58%) were positive and all (100%) cats negative by this test. Polymerase chain reaction detected Leishmania spp. in 100% of dog and cat samples from Botucatu but found all the cats from Campo Grande to be negative. On the other hand, 36 dogs from Campo Grande were positive (72%) by the same technique. Immunofluorescent antibody test in Botucatu found 100% of dogs and cats non-reactive, while in Campo Grande, it detected positivity in 32 dogs (64%) and 15 cats (30%). CONCLUSIONS: The results show the importance of not only continuous epidemiological surveillance in areas not endemic for leishmaniasis, but also research for accurate diagnosis of this zoonosis.

Evaluation of canine and feline leishmaniasis by the association of blood culture, immunofluorescent antibody test and polymerase chain reaction

This study aimed to evaluate the occurrence of Leishmania spp. in dogs and cats from Botucatu, São Paulo state, and Campo Grande, Mato Grosso do Sul state, Brazil, by the association of three diagnostic tests: blood culture in liver infusion tryptose medium, immunofluorescent antibody test and polymerase chain reaction. Fifty blood samples of dogs and cats from the Center for Zoonosis Control in Campo Grande, an area endemic for canine visceral leishmaniasis, were collected randomly, as well as canine and feline blood samples from the Municipal Kennel and Animal Protection Association in Botucatu, currently considered a transmission-free, non-endemic area.

Evaluation of canine and feline leishmaniasis by the association of blood culture, immunofluorescent antibody test and polymerase chain reaction

This study aimed to evaluate the occurrence of Leishmania spp. in dogs and cats from Botucatu, São Paulo state, and Campo Grande, Mato Grosso do Sul state, Brazil, by the association of three diagnostic tests: blood culture in liver infusion tryptose medium, immunofluorescent antibody test and polymerase chain reaction. Fifty blood samples of dogs and cats from the Center for Zoonosis Control in Campo Grande, an area endemic for canine visceral leishmaniasis, were collected randomly, as well as canine and feline blood samples from the Municipal Kennel and Animal Protection Association in Botucatu, currently considered a transmission-free, non-endemic area.

Coinfection by Toxoplasma gondii and Leishmania spp. in domestic cats (Felis catus) in State of Mato Grosso do Sul.

INTRODUCTION: Leishmaniasis and toxoplasmosis are important to public health. METHODS: Antibodies for Toxoplasma gondii and Leishmania spp. were evaluated in cats from Campo Grande, State of Mato Grosso do Sul, Brazil, a region endemic for canine visceral leishmaniasis. Serum samples from 50 asymptomatic cats were titrated for T. gondii by the immunofluorescence antibody test and modified agglutination test and for Leishmania spp. by the immunofluorescence antibody test. RESULTS: These two agents coinfected two (4%) of the 50 tested animals. CONCLUSIONS: These findings demonstrate the concomitant presence of two important zoonoses in cats from Brazilian endemic regions for canine visceral leishmaniasis.

Hemoculture and Polymerase Chain Reaction Using Primers TCZ1/TCZ2 for the Diagnosis of Canine and Feline Trypanosomiasis.

Introduction. American trypanosomiasis, also known as Chagas disease, is a zoonosis caused by Trypanosoma cruzi (T. cruzi). Dogs and cats participate actively in this parasite's transmission cycle. This study aimed at evaluating the occurrence of T. cruzi in dogs and cats from Botucatu, SP, Brazil, as well as at evaluating the technique of hemoculture in LIT (liver infusion tryptose) medium by polymerase chain reaction (PCR). Methods. Blood samples were collected from 50 dogs and 50 cats in Botucatu-SP, Brazil. For hemoculture, the samples were inoculated in LIT medium, and readings were performed for four months. Upon completion of such period, all the hemocultures were processed for parasitic DNA extraction. The PCR reactions were performed by using primers TCZ1/TCZ2. Results. Ten dogs and ten cats (20%) were positive to PCR, and four dogs and three cats (7%) were positive to hemoculture. Only in a one cat sample (1%) there was confirmation of positive hemoculture by PCR for T. cruzi. Conclusions. Results showed that PCR was a suitable tool for the confirmation of the parasite detection in hemoculture samples, and that dogs and cats from Botucatu, SP, Brazil, are maintaining the role of household reservoirs of T. cruzi, which reinforces the need for constant epidemiologic surveillance for this zoonosis.

Leishmania spp. and/or Trypanosoma cruzi diagnosis in dogs from endemic and nonendemic areas for canine visceral leishmaniasis.

Due to the phylogenetic similarity between Leishmania spp. and Trypanosoma cruzi (T. cruzi), serological cross-reactions and false-positive results are quite common. This study aimed to elucidate canine leishmaniasis and trypanosomiasis diagnosis by the indirect fluorescent antibody test (IFAT) on serum samples, and direct parasitological examination and polymerase chain reaction (PCR) in liver and spleen samples. One hundred dogs from Zoonosis Control Center (ZCC) in Bauru, SP, an endemic area for visceral leishmaniasis (VL), and 100 dogs from the Dog Warden Service in Botucatu, SP, a nonendemic area for VL, were studied. IFAT showed positive results for Leishmania spp. in 65% of canine serum samples from Bauru while 40% of the samples were positive for T. cruzi by this test. All samples from Botucatu were negative for leishmaniasis in IFAT, and only 4% were positive for T. cruzi. Out of 200 serum samples tested, 33 (16.5%) showed positive serological results for both the parasites. Direct parasitological examination and PCR found, respectively, 59% and 76% of the liver samples and 51% and 72% of the spleen samples of dogs from Bauru positive for Leishmania spp. Twenty-six (78.8%) of 33 dogs that showed anti-Leishmania spp. and anti-T. cruzi antibodies also tested positive by direct parasitological examination and PCR for Leishmania spp., which indicates that these dogs presented leishmaniasis. No liver or spleen sample from the 200 dogs analyzed showed a positive PCR result for T. cruzi. These findings support the occurrence of cross-reactions between Leishmania spp. and T. cruzi in IFAT; they also corroborate the need for simultaneous PCR and/or parasitological examination to establish canine leishmaniasis (CL) diagnosis.

Avaliação da reatividade cruzada entre antígenos de Leishmania spp e Trypanosoma cruzi na resposta sorológica de cães pela técnica de imunofluorescência indireta (RIFI) / Cross reaction evaluation of Leishmania spp and Trypanosoma cruzi antigens in dogs’ serologic response by indirect immunofluorescence test (IIF)

A leishmaniose visceral (LV) é uma zoonose causada por protozoários do gênero Leishmania. O cão é o principal reservatório do parasito, especialmente em áreas urbanas. A Reação de Imunofluorescência Indireta (RIFI) é comumente empregada para o diagnóstico da leishmaniose visceral canina (LVC), baseada na detecção de anticorpos contra o parasito. Entretanto, reações cruzadas com Trypanosoma cruzi podem ocorrer à sorologia. Com o objetivo de avaliar as reações cruzadas entre os antígenos de Leishmania spp. e de T.cruzi, foram colhidas 150 amostras de sangue de cães positivos para LVC em inquérito epidemiológico e os soros foram testados pela RIFI. Os cães foram submetidos à eutanásia no Centro de Controle de Zoonoses de Bauru (SP), área endêmica para LV. Outras 150 amostrasde sangue de cães foram colhidas em Botucatu (SP), área não endêmica para LV, e os soros foram também testados pela RIFI. Os soros de cães procedentes de Bauru resultaram positivos, tanto para Leishmania spp. quanto para T.cruzi, demonstrando uma grande incidência de reações cruzadas, reforçando a necessidade da confirmação diagnóstica por outras técnicas. As amostras de soros de cães procedentes de Botucatu (SP), pela técnica de RIFI, demonstraram baixa prevalência de resultados positivos para Leishmania spp. e para T.cruzi. Entretanto,apesar do reduzido número de resultados positivos à sorologia para ambos parasitos, a investigação sorológica e epidemiológica para LVe doença de Chagas em cães de Botucatu deve ser mantida, considerando a importância do cão como reservatório doméstico no contexto destas zoonoses.

Visceral Leishmaniasis (VL) is a zoonosis caused by Leishmania spp. protozoa. Dog is the main parasite’s reservoir, especially in urban areas. Indirect Immunofluorescent Antibody Test (IFAT) is commonly used for canine visceral leishmaniasis (CVL) diagnosis, by detection of antibodies against the parasite. However, Trypanosoma cruzi (T.cruzi) cross reactions can occur in serological diagnosis. In order to evaluate the occurrence of cross reactions between antigens of Leishmania spp. and T.cruzi, 150 blood samples of CVL epidemiological inquiry positive dogs were collected and sera were tested by IFAT. Dogs were culled at Zoonosis Control Center of Bauru (SP), an endemic area for VL. Another 150 dogs’ blood samples were collected in Botucatu (SP), a non endemic area for LV, and será were also tested by IFAT. Serum samples of dogs from Bauru were positive, both for Leishmania spp. and for T. cruzi, showing high cross-reactions incidence, reinforcing the need of diagnosis confirmation by other tests. Serum samples of dogs from Botucatu demonstrated low prevalence of positive results by IFAT, both for Leishmania spp. and T.cruzi. However, despite the low number of positive serological results for these parasites, the epidemiological and serological investigation for LV and Chagas disease in dogs from Botucatu must be kept, considering the importance of dog as domestic reservoir for both parasites.