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Leishmaniasis is a zoonotic disease with worldwide distribution. In the Americas, the causative agent of the visceral form is the protozoa Leishmania (Leishmania) infantum. Transmission to the host or vertebrate reservoir occurs through the bite of infected arthropod females like Lutzomyia longipalpis. The epidemiological connection between the infection in dogs and humans generate constant studies about the relationship between the parasite and the canine host, including the development of methods and tests for the detection and quantification ofLeishmania (L.) infantum. Both conventional PCR (cPCR) and quantitative PCR (qPCR) can be used in the diagnosis of the parasite. Dropet Digital PCR (ddPCR) is another useful tool. Knowing the parasite load and its relationship with the clinical signs of naturally infected dogs is useful in research development and for establishing treatments that reduce the transmission of the disease. In this study, thirty-nine clinical samples of spleen from dogs naturaly infected by L. infantum were collected after necropsy. Two molecular tools were used to quantify the parasite load (qPCR and ddPCR) and there was 100% agreement in the results of the them. The tools developed in this work are important for the detection of L. infantum in dogs and humans. Droplet Digital PCR does not require a standard curve and is easy to standardize. In such manner, this new tool can generate more in-depth information in the broad debate about parasitic loads and the pathogenesis of leishmaniasis.

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Dogs are the most important reservoir of Leishmania infantum, the causal agent of visceral leishmaniasis in Brazil. Although lymphoid tissue is the most important biological tissue where amastigotes can be found, this paper describes the presence of L. infantum DNA in the milk of a lactating naturally infected female dog. This finding suggests the need for further studies to elucidate whether breastfeeding can be a route of infection.

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During the COVID-19 pandemic, reductions in heart failure (HF) hospitalizations have been widely reported, and there is an urgent need to understand how HF care has been reorganized in countries with different infection levels, vaccination rates and healthcare services. The OPTIMIZE Heart Failure Care program has a global network of investigators in 42 countries, with first-hand experience of the impact of the pandemic on HF management in different care settings. The national coordinators were surveyed to assess: 1) the challenges of the COVID-19 pandemic for continuity of HF care, from both a hospital and patient perspective; 2) the organizational changes enacted to ensure continued HF care; and 3) lessons learned for the future of HF care. Contributions were obtained from 37 national coordinators in 29 countries. We summarize their input, highlighting the issues raised and using the example of three very different settings (Italy, Brazil, and Taiwan) to illustrate the similarities and differences across the OPTIMIZE program.

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Epidemiological studies of leishmaniasis in areas of great human influence and environmental change serve as important tools for the implementation of effective control plans. Mining is currently a major economic activity in Brazil with the municipality of Pains, in the state of Minas Gerais, being one of the main lime producing municipalities in the country. This study aimed to map areas of potential transmission risks within the municipality of Pains using an epidemiological approach in association with the ecological study of sand flies. Twelve samplings carried out between May 2015 and April 2016 collected a total of 12,728 sandflies, comprising 2,854 females (22.42%) and 9,874 males (77.58%), of 20 species belonging to ten genera. The most abundant species was Lutzomyia longipalpis (80%). Leishmania DNA was detected in seven pools of female sand flies with an infection rate of 0.37%. Geoprocessing and the use of maps revealed that vector sand flies are distributed throughout the urban area, as are cases of canine and human leishmaniasis. However, the greatest abundances of sand flies were at sampling points at the border of the urban area. Higher densities of sand flies and the presence of Leishmania DNA may be correlated with extensive degradation by limestone mining. Integrated and multidisciplinary research approaches are necessary to better understand how the impacts of environmental change influence these insect vectors of leishmaniasis.

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Canine visceral leishmaniasis (CVL) is caused by Leishmania infantum and is endemic in many areas of southeastern Brazil. We have hypothesized that the prevalence of infection by L. infantum in dogs housed in open-admission animal shelters is beyond the range of 3.4 - 9.6% reported among dogs domiciled in similar CVL-endemic areas. Hence, this study aimed to determine the rate of L. infantum infection among dogs maintained in shelters and to investigate the epidemiology of CVL in such environments by analyzing hematological and biochemical parameters. A total of 627 dogs from 17 different shelters across the State of Minas Gerais were screened using the Dual-Path Platform test and enzyme-linked immunosorbent assay and 211 (33.6%) were found to be seropositive in both tests. Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) was performed on skin, bone marrow and lymphoid tissues of 118 seropositive dogs with inconclusive CVL clinical diagnosis and, of these, 78 (66.1%) were PCR+ for L. infantum and 7 (5.9%) were PCR+ for L. amazonensis. One dog presented a PCR-RFLP profile that was consistent with co-infection by both parasites. Leishmania amazonensis DNA was detected in skin samples of six single-infected dogs and this constitutes a novel finding. Dogs infected only with L. amazonensis were less debilitated than those infected by L. infantum, which showed typical clinical manifestations of CVL. The co-infected dog showed only mild clinical signs. The results presented herein not only support our original hypothesis but also suggest that dogs are potential reservoirs of L. amazonensis. Public health authorities should acknowledge their responsibility towards animals in collective shelters, recognize that they are potential foci of zoonotic diseases, and establish proper functioning directives to minimize transmission to humans and to other dogs.

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Yellow fever (YF), caused by the yellow fever virus (YFV), is an emerging viral zoonosis that affects humans and non-human primates (NHP). In South America, YF is naturally maintained through enzootic/sylvatic cycles involving NHPs and mosquitoes (Haemagogus and Sabethes). In this study, we retrospectively analyzed wildlife rodents to better understand their role in a potential alternative YF sylvatic cycle. The plaque reduction neutralization test was performed to detect anti-YFV antibodies, while qPCR targeting the NS5 region of flaviviruses and standard PCR targeting the CprM region were applied to detect YFV RNA in tissue and blood samples. YFV was not evidenced in any of the tested samples. These findings provide additional information regarding sylvatic YFV and emphasize the importance of YFV surveillance in wild animals as potential reservoirs/hosts given the well-established enzootic cycle in the studied areas, mainly in the Atlantic Forest.

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Leishmaniases comprise a spectrum of diseases caused by protozoan parasites of the genus Leishmania, with some species of rodents being incriminated as reservoirs. The capybara is the largest extant rodent species in the world and is widely distributed in South America. The occurrence of infection by Leishmania spp. was investigated in capybaras captured in Brazil during 2015­2019 from established populations in five highly anthropic areas of the state of São Paulo and two natural areas of the states of Mato Grosso and Mato Grosso do Sul. A total of 186 individuals were captured and subjected to abdominal skin biopsy. All skin samples were Leishmania kDNA-negative, suggesting that capybaras have no role in the transmission cycles of Leishmania species in the studied areas despite the well-known role of other rodents in the life cycle of Leishmania spp.(AU)

As leishmanioses compreendem um espectro de doenças causadas por protozoários do gênero Leishmania e algumas espécies de roedores são incriminadas como reservatórios de Leishmania spp. As capivaras compreendem a maior espécie de roedores existentes e são amplamente distribuídas na América do Sul. Para investigar a ocorrência de infecção por Leishmania spp. em capivaras, durante os anos de 2015-2019 capivaras foram capturadas em cinco áreas antrópicas do estado de São Paulo e em duas áreas naturais dos estados do Mato Grosso e do Mato Grosso do Sul, todos esses ambientes com populações de capivaras estabelecidas. Um total de 186 indivíduos foram capturados e submetidos à biópsia de pele abdominal. Todas as amostras de pele foram negativas para o alvo kDNA, assim, os dados sugerem que nas áreas estudadas as capivaras não têm papel no ciclo de transmissão de espécies de Leishmania spp., apesar do papel bem conhecido de outros roedores no ciclo de vida de Leishmania spp.(AU)

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Dogs are the main reservoirs in the domestic transmission cycle of visceral leishmaniasis, and the diagnosis is essential for the effectiveness of the control measures recommended by the Brazilian Ministry of Health. We assessed the diagnostic performance of the ELISA-Vetlisa/BIOCLIN prototype with serum samples from 200 dogs, in triplicate, including symptomatic, oligosymptomatic, asymptomatic, and healthy dogs, originated by two distinct panels (A and B) characterized by parasitological tests as the reference standard. In this study, the prototype kit showed a 99% sensitivity (95%CI: 94.5-100.0) and a 100% specificity (95%CI: 96.4-100.0). The sensitivity of the prototype kit did not vary significantly with the clinical status of the dogs. Considering the final result classification (positive or negative), agreement between the results of repeated tests was almost perfect (kappa = 0.99; 95%CI: 0.98-1.00). ELISA-Vetlisa/BIOCLIN is a promising option for the serological diagnosis of canine visceral leishmaniasis in Brazil.

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Abstract: Dogs are the main reservoirs in the domestic transmission cycle of visceral leishmaniasis, and the diagnosis is essential for the effectiveness of the control measures recommended by the Brazilian Ministry of Health. We assessed the diagnostic performance of the ELISA-Vetlisa/BIOCLIN prototype with serum samples from 200 dogs, in triplicate, including symptomatic, oligosymptomatic, asymptomatic, and healthy dogs, originated by two distinct panels (A and B) characterized by parasitological tests as the reference standard. In this study, the prototype kit showed a 99% sensitivity (95%CI: 94.5-100.0) and a 100% specificity (95%CI: 96.4-100.0). The sensitivity of the prototype kit did not vary significantly with the clinical status of the dogs. Considering the final result classification (positive or negative), agreement between the results of repeated tests was almost perfect (kappa = 0.99; 95%CI: 0.98-1.00). ELISA-Vetlisa/BIOCLIN is a promising option for the serological diagnosis of canine visceral leishmaniasis in Brazil.

Resumo: Os cães são os principais reservatórios do ciclo de transmissão domiciliar da leishmaniose visceral, e o diagnóstico é essencial para a efetividade das medidas de controle recomendadas pelo Ministério da Saúde. Os autores avaliam o desempenho diagnóstico do protótipo da ELISA-Vetlisa/BIOCLIN em amostras sorológicas de 200 cães, em triplicata, incluindo cães sintomáticos, oligossintomáticos e saudáveis, com dois painéis distintos (A e B) caracterizados por testes parasitológicos enquanto referência. No estudo, o kit-protótipo mostrou sensibilidade de 99% (IC95%: 94,5-100,0) e especificidade de 100% (IC95%: 96,4-100,0). A sensibilidade do kit-protótipo não variou de maneira significativa de acordo com o estado clínico dos cães. Considerando a classificação final dos resultados (positivo ou negativo), a concordância entre os resultados dos testes em triplicata foi quase perfeita (kappa = 0,99; IC95%: 0,98-1,00). O protótipo ELISA-Vetlisa/BIOCLIN tem o potencial de ser utilizada para o diagnóstico sorológico da leishmaniose visceral canina no Brasil.

Resumen: Los perros son los principales reservorios en el ciclo de transmisión doméstica de la leishmaniasis visceral, por ello el diagnóstico es esencial para la efectividad de las medidas de control recomendadas por el Ministerio de Salud de Brasil. Evaluamos el desempeño diagnóstico de ELISA-Vetlisa/BIOCLIN prototipo con muestras de sérum de 200 perros, en triplicado, incluyendo sintomático, oligosintomático, asintomático y perros sanos, originadas por dos paneles distintos (A y B), caracterizados por test parasitológicos como referencia estándar. En este estudio, el kit prototipo mostró un 99% de sensibilidad (IC95%: 94,5-100,0) y un 100% de especificidad (IC95%: 96,4-100,0). La sensibilidad del kit prototipo no varió significativamente con el estatus clínico de los perros. Considerando la clasificación final del resultado (positiva o negativa), el acuerdo entre los resultados de los tests repetidos fue casi perfecto (kappa = 0,99; IC95%: 0,98-1,00). ELISA-Vetlisa/BIOCLIN tiene potencial para ser usado para el diagnóstico serológico de la leishmaniasis visceral canina en Brasil.

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This study aimed to describe the sand fly fauna and detect trypanosomatids in these insects from Casa Branca, state of Minas Gerais, Brazil, an endemic area of both visceral (VL) and tegumentary leishmaniasis (TL). Sand flies were collected bimonthly from May 2013 to July 2014, using automatic light traps exposed for three consecutive nights in peridomiciliary areas of nine houses with previous reports of VL and TL. ITS1-PCR and DNA sequencing were performed for trypanosomatids identification. A total of 16,771 sand flies were collected belonging to 23 species. The most abundant species was Nyssomyia whitmani (Antunes & Coutinho, 1939) (70.9%), followed by Lutzomyia longipalpis (Lutz & Neiva, 1912) (15.2%) and Migonemyia migonei (França, 1920) (9.1%). Leishmania amazonensis DNA was detected in Ny. whitmani (four pools) and Le. braziliensis DNA was detected in Psychodopygus lloydi (one pool). In seven pools of Ny. whitmani and in one pool of Lu. longipalpis positive for Leishmania DNA, the parasite species was not determined due to the low quality of the sequences. Moreover, DNA of Herpetomonas spp. was detected in Ny. whitmani (two pools) and Cortelezzii complex (one pool). DNA of Crithidia spp. was detected in Ny. whitmani and Ps. lloydi (both one pool). Our results suggest that Ny. whitmani may be involved in the transmission of Le. amazonensis in the study area. The molecular detection of Le. amazonensis suggests the presence of this species in a sylvatic cycle between vertebrate and invertebrate hosts in the region of Casa Branca. Our data also reveal the occurrence of other non-Leishmania trypanosomatids in sand flies in Casa Branca District.

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The diagnosis of canine visceral leishmaniasis (CVL) has been a problem for public health services due to the variety of clinical signs similar to other diseases and low sensitivity and specificity of available tests. In this sense, our main objective was to develop a simple, rapid, and accurate quantitative real-time PCR (qPCR) diagnosis for CVL. Thus, low-invasive samples from bone marrow (BM), popliteal lymph nodes (PLN), and conjunctival swabs (CS) were selected from negative and VL-positive dogs, using as gold standard, immunological and parasitological tests performed with different tissues. Oligonucleotides for Leishmania infantum kDNA were designed and the limit of quantification and amplification efficiency of the qPCR were determined using tissue-specific standards produced with DNA from those different tissues, mixed with DNA from a known amount of L. infantum promastigotes. Endogenous control was used to validate a comparative Ct method, and tissue parasite concentrations were estimated by comparison with tissue-specific reference standard samples. The overall analysis of the qPCR data suggests the following ranking for tissue choice: PLN > BM > CS. Finally, we have concluded that this molecular approach simplifies and accelerates the quantitative diagnostic process because it is easy to perform, requiring no DNA dosing or standard curve application, and it shows good diagnostic parameters, especially when using popliteal lymph node samples.

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Los aneurismas del seno de Valsalva son anomalías infrecuentes, ocasionadas por la falta de continuidad entre la túnica media de la aorta y el anillo valvular. Suelen ser asintomáticos mientras estén íntegros, la mayoría se diagnostica sucesivamente a una rotura. Son más frecuentes en el sexo masculino y su rotura afecta más a jóvenes adultos. Pueden ser causa de insuficiencia cardiaca y en algunos casos llegan a presentarse como muerte súbita. Su diagnóstico requiere estudios de imagen y su tratamiento generalmente es quirúrgico. Se presenta el caso de un paciente femenino de 18 años que consultó por síntomas de insuficiencia cardiaca. Al examen físico se encontró hipotensa, con choque de punta desplazado hacia la izquierda, soplo auscultado en todos los focos e irradiado hacia la izquierda, ingurgitación yugular y ascitis. La radiografía de tórax reveló cardiomegalia y el ecocardiograma transtorácico evidenció rotura de aneurisma del seno de Valsalva coronario derecho. La sospecha de rotura de aneurisma del seno de Valsalva ante síntomas de insuficiencia cardiaca y soplo, permite la corrección exitosa del defecto.

Aneurysms of the sinus of Valsalva are infrequent anomalies caused by discontinuity between middle tunic of aorta and the valvular ring. Generally, they are asymptomatic while they are intact, most of them are diagnosed after to a rupture. They affect with more frequency males and its rupture mostly occur in young adults; this defect can be a cause of heart failure. In some cases, can occur as sudden death. Its diagnosis requires imaging studies and its treatment is usually surgical. It is presented the case of an 18 years old female patient, who consulted for symptoms of heart failure. Upon physical examination, It was found hipotension with a displaced tip shock, murmur auscultated in all auscultatory sites and it was irradiated to left armpit, presence of jugular ingurgitation and ascites. Chest radiography revealed cardiomegaly and the transthoracic echocardiogram showed rupture of the right coronary sinus of Valsalva aneurysm. Suspect the rupture of the sinus of Valsalva aneurysm at the presence of heart failure symptoms and murmur, allows the successful correction of the defect.

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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.(AU)

O papel dos gatos no ciclo epidemiológico da leishmaniose ainda não está claro. Para entender melhor a ocorrência de leishmaniose em gatos, estudou-se a frequência de Leishmania em amostras de soro de 100 gatos, os quais vivem em uma região endêmica para leishmaniose canina e humana, por métodos sorológicos, parasitológicos e moleculares. Dos 100 gatos, 54 foram soropositivos para anticorpos de Leishmania por teste de anticorpos de imunofluorescência. Nenhum dos aspirados de medula óssea coletados desses gatos mostrou-se positivo para o parasita em cultura, ou após a realização da reação em cadeia da polimerase (PCR). Amostras de biópsia das orelhas também foram negativas para Leishmania submetidas a PCR. Esses achados indicam que na região estudada endêmica para leishmaniose canina, os gatos podem se infectar por Leishmania; ou que a reação cruzada com anticorpos contra outros parasitas aumenta a frequência de soropositividade; ou que os gatos respondem à infecção por Leishmania produzindo anticorpos quando poucos ou nenhum parasita estão presentes na medula óssea e em amostras de tecido. Em geral, os resultados sugerem que os gatos podem ser estar infectados por Leishmania spp. No entanto, não foi possível demonstrar parasitismo felino. Essas descobertas evidenciam a necessidade de estudar a leishmaniose em gatos, uma vez que, como os flebotomíneos se alimentam em gatos, e esses animais podem atuar como um reservatório para o parasita.(AU)

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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.

Resumo O papel dos gatos no ciclo epidemiológico da leishmaniose ainda não está claro. Para entender melhor a ocorrência de leishmaniose em gatos, estudou-se a frequência de Leishmania em amostras de soro de 100 gatos, os quais vivem em uma região endêmica para leishmaniose canina e humana, por métodos sorológicos, parasitológicos e moleculares. Dos 100 gatos, 54 foram soropositivos para anticorpos de Leishmania por teste de anticorpos de imunofluorescência. Nenhum dos aspirados de medula óssea coletados desses gatos mostrou-se positivo para o parasita em cultura, ou após a realização da reação em cadeia da polimerase (PCR). Amostras de biópsia das orelhas também foram negativas para Leishmania submetidas a PCR. Esses achados indicam que na região estudada endêmica para leishmaniose canina, os gatos podem se infectar por Leishmania; ou que a reação cruzada com anticorpos contra outros parasitas aumenta a frequência de soropositividade; ou que os gatos respondem à infecção por Leishmania produzindo anticorpos quando poucos ou nenhum parasita estão presentes na medula óssea e em amostras de tecido. Em geral, os resultados sugerem que os gatos podem ser estar infectados por Leishmania spp. No entanto, não foi possível demonstrar parasitismo felino. Essas descobertas evidenciam a necessidade de estudar a leishmaniose em gatos, uma vez que, como os flebotomíneos se alimentam em gatos, e esses animais podem atuar como um reservatório para o parasita.

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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.

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The aim of this study was to evaluate the relationship between naturally occurring Leishmania spp. infections in dogs (Canis familiaris) and the practical implications of the use of serological and molecular methods to confirm diagnoses. The study population consisted of 96 domestic dogs in southeastern Brazil. Serum samples were tested for the presence of anti-Leishmania immunoglobulin G (IgG) antibodies using four commercial canine visceral leishmaniasis kits. Dogs confirmed positive by immunofluorescence antibody test (IFAT) were culled and samples from mesenteric lymph nodes, spleen border, bone marrow and ear skin were taken and submitted to DNA extraction. PCR reactions were performed using primers that amplify a 300-350 bp fragment of the Leishmania ribosomal internal transcribed spacer 1 (ITS1) region. The ITS1 amplified products were analyzed by PCR-RFLP using Hae III restriction endonuclease. To confirm the Leishmania species detected by PCR, each purified sample was sequenced in duplicate. Of the 96 serum samples submitted to serological assays, 8 (8.3%) tested positive for Leishmania by IFAT, 4 (4.1%) by ELISA, 2 (2.1%) by rK39 RDT and 7 (7.3%) by DPP. Four of these infected dogs (50%) were found to be infected only by Leishmania braziliensis or Leishmania amazonensis, and their serum samples tested positive by IFAT and DPP. These findings demonstrate for the first time that cross-reactivity of L. braziliensis and L. amazonensis infection in dogs can be found using the DPP serum test. This is the first record of Leishmania (Leishmania) amazonensis confirmed by a specific molecular marker in dogs (Canis familiaris) from Belo Horizonte, Brazil.

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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.

Resumo O papel dos gatos no ciclo epidemiológico da leishmaniose ainda não está claro. Para entender melhor a ocorrência de leishmaniose em gatos, estudou-se a frequência de Leishmania em amostras de soro de 100 gatos, os quais vivem em uma região endêmica para leishmaniose canina e humana, por métodos sorológicos, parasitológicos e moleculares. Dos 100 gatos, 54 foram soropositivos para anticorpos de Leishmania por teste de anticorpos de imunofluorescência. Nenhum dos aspirados de medula óssea coletados desses gatos mostrou-se positivo para o parasita em cultura, ou após a realização da reação em cadeia da polimerase (PCR). Amostras de biópsia das orelhas também foram negativas para Leishmania submetidas a PCR. Esses achados indicam que na região estudada endêmica para leishmaniose canina, os gatos podem se infectar por Leishmania; ou que a reação cruzada com anticorpos contra outros parasitas aumenta a frequência de soropositividade; ou que os gatos respondem à infecção por Leishmania produzindo anticorpos quando poucos ou nenhum parasita estão presentes na medula óssea e em amostras de tecido. Em geral, os resultados sugerem que os gatos podem ser estar infectados por Leishmania spp. No entanto, não foi possível demonstrar parasitismo felino. Essas descobertas evidenciam a necessidade de estudar a leishmaniose em gatos, uma vez que, como os flebotomíneos se alimentam em gatos, e esses animais podem atuar como um reservatório para o parasita.

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Leishmaniases are parasitic diseases transmitted to mammalian hosts by sand fly vectors (Diptera: Psychodidae). Despite the increasing occurrence of visceral and cutaneous leishmaniasis cases in urban centers, their transmission still occur primarily in wild environments and may be associated with professional activities and recreation, such as ecotourism. The Reserva Particular do Patrimônio Natural Santuário do Caraça (RPPNSC) is one of the largest ecotourism attractions in the State of Minas Gerais, Brazil, and comprises an area of environmental preservation with 11,233 hectares presenting a transitional vegetation between Cerrado and Atlantic Forest. The present study describes the abundance of small mammals in RPPNSC, the isolation and identification of Leishmania in five wild animals. Small mammals were bimonthly trapped along 6 trails within the RPPNSC with 10 Tomahawk traps each. Two trails were located in peridomiciliary areas near tourist lodging facilities, and four trails were located at sites visited by tourists in forest areas. The most prevalent species were Akodon cursor, Cerradomys subflavus and Oligoryzomys nigripes. Six isolates of Leishmania were obtained from these animals and identified as Leishmania braziliensis through HSP70-PCR RFLP method. Leishmania spp. DNA was detected by kDNA-PCR method and isolated by biphasic culture. Studies point to some of the captured species as potential wild reservoirs of Leishmania, suggesting they may be involved in the transmission cycle in these wild environments.

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RESUMO

Knowledge of potential reservoirs of Leishmania spp. in an anthropic environment is important so that surveillance and control measures can be implemented. The aim of this study was to investigate the infection by Leishmania in small mammals in an area located in Minas Gerais, Brazil, that undergoes changes in its natural environment and presents autochthonous human cases of cutaneous leishmaniasis (CL) and visceral leishmaniasis (VL). For the capture of the animals, Sherman and Tomahawk traps were used and distributed in the peridomicile of houses with reports of autochthonous cases of CL or VL. Six catches were carried out on two consecutive nights with intervals of two months during one year and samples of spleen, liver, tail skin, ear skin and bone marrow of the animals were obtained. Parasitological and molecular methods were used to detect the infection. Identification of the Leishmania species was performed by PCR RFLPhsp70. Twenty five animals of four species were captured: ten Rattus rattus, nine Didelphis albiventris, five Cerradomys subflavus and one Marmosops incanus. In the PCR-hsp70, five animals were positive (20%). The Leishmania species identified in PCR-RFLPhsp70 were: Leishmania braziliensis in D. albiventris (2), C. subflavus (1) and R. rattus (1) and Leishmania infantum in R. rattus (1). The highest positivity rate for L. braziliensis was obtained in the liver samples. The spleen was the only tissue positive for L. infantum. It was isolated in culture medium L. braziliensis from two samples (liver and spleen) of R. rattus. This is the first record of isolation of L. braziliensis from R. rattus in the southeastern region of Brazil. These results are relevant to the knowledge of the epidemiology of leishmaniasis in the region, mainly in the investigation of the presence of hosts and possible reservoirs of the parasite.

Assuntos