ABSTRACT
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)
Subject(s)
Animals , Protozoan Infections, Animal/diagnosis , Rodentia/microbiology , Leishmaniasis/diagnosis , Skin/microbiology , Biopsy/instrumentation , Brazil , DNA, Kinetoplast/analysis , Leishmania/geneticsABSTRACT
Chagas disease and leishmaniasis are neglected tropical diseases caused by the protozoan parasites Trypanosoma cruzi and Leishmania spp., respectively. They are among the most important parasitic diseases, affecting millions of people worldwide, being a considerable global challenge. However, there is no human vaccine available against T. cruzi and Leishmania infections, and their control is based mainly on chemotherapy. Treatments for Chagas disease and leishmaniasis have multiple limitations, mainly due to the high toxicity of the available drugs, long-term treatment protocols, and the occurrence of drug-resistant parasite strains. In the case of Chagas disease, there is still the problem of low cure rates in the chronic stage of the disease. Therefore, new therapeutic agents and novel targets for drug development are urgently needed. Antioxidant defence in Trypanosomatidae is a potential target for chemotherapy because the organisms present a unique mechanism for trypanothione-dependent detoxification of peroxides, which differs from that found in vertebrates. Cellular thiol redox homeostasis is maintained by the biosynthesis and reduction of trypanothione, involving different enzymes that act in concert. This study provides an overview of the antioxidant defence focusing on iron superoxide dismutase A, tryparedoxin peroxidase, and ascorbate peroxidase and how the enzymes play an important role in the defence against oxidative stress and their involvement in drug resistance mechanisms in T. cruzi and Leishmania spp.
ABSTRACT
Abstract Visceral leishmaniasis (VL) is a neglected and endemic zoonosis that occurs throughout Brazil; nevertheless, few studies have focused on the early detection of the disease. The municipality of Ourinhos is a non-receptive, silent and vulnerable area for VL, where the seroprevalence of this disease has so far not been investigated. The present study aimed to determine the seroprevalence of canine VL in Ourinhos-SP, and to identify the presence of risk factors. Blood samples were obtained from 604 dogs during a rabies vaccination campaign together with application of a socioeconomic questionnaire, environmental and animal characteristics and tutor's knowledge about the disease. The samples were subjected to indirect ELISA and new samples were collected from reactive and suspect animals, including whole blood and lymph node aspiration evaluated by parasitological method, complete blood count and PCR. No animal was diagnosed as positive based on the combination of direct and indirect tests and the tutors' answers indicated little knowledge about leishmaniasis, being often confused with other diseases transmitted by arthropods; hence, according to the proposed methods, the presence of canine leishmaniasis in the city of Ourinhos was not confirmed and health education campaigns about the disease should be carried out.
Resumo A leishmaniose visceral (LV) é uma zoonose negligenciada e endêmica presente em todas as regiões do Brasil, mas mesmo assim poucos estudos têm objetivado a detecção inicial da doença. O município de Ourinhos - SP é uma área não receptiva, silenciosa e vulnerável à LV, não havendo até o momento estudos que tenham investigado a soroprevalência no município. Nesse sentido, o presente estudo objetivou determinar a soroprevalência da LV canina em Ourinhos-SP, bem como associar a presença de fatores de risco. Amostras sanguíneas de 604 cães foram obtidas juntamente com a aplicação de questionário socioeconômico, características ambientais e dos animais e conhecimento sobre a doença. As amostras foram submetidas à sorologia por ELISA e novas amostras coletadas de cães reagentes ou suspeitos foram analisadas por método parasitológico direto, hemograma e PCR. Nenhum animal foi considerado positivo na combinação de testes direto e indireto, e as respostas dos tutores indicaram pouco conhecimento sobre a leishmaniose, sendo muitas vezes confundida com outras doenças transmitidas por artrópodes. Dessa forma, de acordo com os métodos propostos, a presença de leishmaniose canina, na cidade de Ourinhos, não foi confirmada. Por isso campanhas de educação em saúde sobre a doença deveriam ser realizadas.
Subject(s)
Animals , Dogs , Leishmaniasis/veterinary , Dog Diseases/diagnosis , Dog Diseases/epidemiology , Leishmaniasis, Visceral/diagnosis , Leishmaniasis, Visceral/veterinary , Leishmaniasis, Visceral/epidemiology , Brazil/epidemiology , Seroepidemiologic StudiesABSTRACT
ABSTRACT: Canine visceral leishmaniasis is a systemic, zoonotic disease widely spread in several countries. The disease is caused by Leishmania spp., and the dog is the main reservoir of this parasite. Clinical signs in the muscle skeletal system consist of muscle atrophy, weakness, lameness, abnormal locomotion, osteitis, polyarthritis, heat and swelling of the joints, enlarged local lymph nodes and pain. In this note, a case of canine myositis of the lumbar region associated with Leishmania spp. infection is reported. Clinical signs included weakness, fever, mild dehydration, enlarged mandibular, pre-scapular and popliteal lymph nodes and a large palpable soft mass in the lumbar region, semi-adhered and not painful. Serologic diagnosis resulted reagent by indirect immunofluorescence reaction method. Findings of ultrasonography of the lower back are described, revealing the misalignment of muscle fibers, interspersed with anechoic areas compatible with edema. Local fine needle aspiration cytology was crucial for a definitive diagnosis, revealing amastigote forms. In endemic areas of leishmaniasis, clinicians should consider this disease as a differential diagnosis in the presence of musculoskeletal injuries with no apparent cause.
RESUMO: A leishmaniose canina visceral é uma doença sistêmica, zoonótica e amplamente difundida causada por parasitas do gênero Leishmania spp., sendo o cão importante hospedeiro. Os sinais clínicos de leishmaniose no sistema músculo esquelético se constituem em atrofia muscular, fraqueza, claudicação, locomoção anormal, osteíte, poliartrite, hipertermia, dor e edema das articulações. A presente nota descreve um caso de miosite lombar em cão associada à infecção por Leishmania spp. Os sinais clínicos incluíram fraqueza, febre, desidratação leve, aumento dos linfonodos mandibulares, pré-escapulares e poplíteos e uma grande massa macia palpável na região lombar, semi-aderida e não dolorosa. O diagnóstico sorológico resultou em reagente pelo método da reação de imunofluorescência indireta totalmente diluída. Os achados da ultrassonografia da região lombar são descritos, revelando o desalinhamento das fibras musculares, intercaladas com áreas anecóicas, compatíveis com edema. A citologia local de aspiração por agulha fina foi crucial para o diagnóstico definitivo, revelando formas amastigotas. Nas áreas endêmicas da leishmaniose, deve-se considerar esta doença como diagnóstico diferencial na presença de lesões musculoesqueléticas sem causa aparente.
ABSTRACT
ABSTRACT: Toxoplasmosis, neosporosis, and leishmaniasis are important diseases of worldwide distribution and can affect both pets and humans. Hunting dogs have been trained to hunt domestic and wild animals, which makes them more exposed to parasitic infections. The present study aimed to evaluate the seroprevalence of Toxoplasma gondii, Neospora caninum, and Leishmania spp. in hunting dogs from a rural area in Mato Grosso do Sul, Brazil. Serum samples were collected from 39 American Foxhound dogs, and the sex and age variables were recorded. Serum samples were subjected to an indirect fluorescent antibody test (IFAT) to detect antibodies. Seroprevalence was 35.9%, 15.4%, and 2.6% for Toxoplasma gondii, Neospora caninum e Leishmania spp., respectively. There was no statistical difference between genders for these diseases (P>0.05). Results demonstrated a circulation of these protozoa in hunting dogs in a rural area of the state of Mato Grosso do Sul, which can contribute to the epidemiology of these diseases.
RESUMO: Toxoplasmose, neosporose e leishmaniose são importantes doenças de distribuição mundial e podem afetar tanto os animais de companhia quanto os humanos. Os cães de caça têm sido treinados para caçar animais domésticos e selvagens, o que torna esses animais mais expostos a infecções parasitárias. O presente estudo teve como objetivo avaliar a soroprevalência de Toxoplasma gondii, Neospora caninum e Leishmania spp. em cães de caça de área rural do Mato Grosso do Sul, Brasil. Foram coletadas amostras de soro de 39 cães da raça Foxhound-americano e as variáveis sexo e idade foram registradas. As amostras de soro foram submetidas a reação de imunofluorescência indireta (RIFI) para detecção dos anticorpos. A soroprevalência foi de 35,9%, 15,4% e 2,6% para Toxoplasma gondii, Neospora caninum e Leishmania spp., respectivamente. Não foi observado diferença estatística entre os sexos para todas as doenças (P>0.05). Os resultados demonstram circulação desses protozoários em cães de caça de uma área rural do estado do Mato Grosso do Sul, o que pode contribuir para a epidemiologia dessas doenças.
ABSTRACT
ABSTRACT Cysteine proteinases are well-known virulence factors of Leishmania spp. with demonstrated actions in both experimental mouse infection and human infection. However, studies on these enzymes in canine leishmaniasis are scarce. Here, we show, for the first time, the reactivity of sera from dogs living in an endemic area to a recombinant protein from the COOH-terminal region of cysteine B protease. In this work, enzyme-linked immunosorbent assays were performed using a 14 kDa rcyspep protein obtained through a pET28-a expression system in Escherichia coli. First, 96-well plates were coated with rcyspep (500 ng/well) and incubated with sera from dogs (1:100). Subsequently, IgG antibody detection was performed using rabbit anti-dog IgG antibodies conjugated with peroxidase. Sera from dogs (n = 114), including suspect (n = 30) and positive (n = 50) dogs from a leishmaniasis-endemic area and dogs from a nonendemic area, (n = 34), negative for leishmaniasis, were assessed. The results showed that sera from the suspect (42%) and positive (68%) groups responded differently to the antigen titers tested above the cut-off (Optical Density = 0.166). This finding suggests that the immune response detected against cyspep may be related to clinical disorders present in these animals. Collectively, the data gathered here suggest that cyspep can sensitize the immune systems of dogs from a leishmaniasis-endemic area to elicit a humoral response, an immunological parameter indicating the contribution of this protein in host-parasite interaction.
Subject(s)
Animals , Dogs , Humans , Mice , Rabbits , Leishmaniasis/blood , Dog Diseases/blood , Cysteine Proteases/blood , Leishmania , Enzyme-Linked Immunosorbent Assay , Antibodies, Protozoan , Leishmaniasis/veterinary , Leishmania infantum , Cysteine , Leishmaniasis, VisceralABSTRACT
Abstract INTRODUCTION: In the Belém Metropolitan Region (BMR), Pará State, Brazil, American cutaneous leishmaniasis (ACL) is endemic; however, very little is known regarding its causative agents. Therefore, we used our standard diagnostic approach combined with an RNA polymerase II largest subunit (RNAPOIILS)-polymerase chain reaction (PCR) followed by analysis of restriction fragment length polymorphism (PCR-RFLP) to identify Leishmania spp. ACL agents in this region. METHODS: Thirty-two Leishmania spp. isolates from patients with ACL in the BMR during 1995-2018 were analyzed. Leishmania spp. DNA samples were amplified using the primers RPOR2/RPOF2, and the 615-bp PCR products were subjected to enzymatic digestion using TspRI and HgaI endonucleases. RESULTS: ACL etiological agents in the BMR comprised Leishmania (Viannia) lindenbergi (43.7%) followed by Leishmania (Viannia) lainsoni (34.4%), Leishmania (Leishmania) amazonensis (12.5%), and Leishmania (Viannia) braziliensis (9.4%). CONCLUSIONS: To our knowledge, the results of the study revealed for the first time that L. (V.) lindenbergi and L. (V.) lainsoni are the main ACL agents in BMR.
Subject(s)
Humans , Leishmania braziliensis/genetics , Leishmaniasis, Cutaneous/diagnosis , Leishmaniasis, Cutaneous/epidemiology , Leishmania/genetics , United States , Brazil/epidemiology , Leishmaniasis, CutaneousABSTRACT
Abstract Introduction: The study of the interaction between the parasite, the vector and the mammalian hosts, including man, allows to understand the behavior of the leishmaniases. Objective: To determine the presence of Lutzomyia species and to detect the Leishmania infection in Didelphis marsupialis in an endemic area for visceral leishmaniasis. Materials and methods: Phlebotomine fauna and individuals of D. marsupialis were collected with CDC and Tomahawk™ traps, respectively. The species of Lutzomyia were identified using the Young and Duncan key (1994). Ear and tail biopsies and blood samples from D. marsupialis were taken to identify the Leishmania species by amplifying a fragment of the gene associated with the 70 kD heat shock protein. Results: Seven Lutzomyia species were identified: Lu. evansi, Lu. gomezi, Lu. panamensis, Lu. dubitans, Lu. cayennensis cayennensis, Lu. rangeliana and Lu. trinidadensis. The first three species have epidemiological importance in Colombia because of their implications in the transmission of the Leishmania parasite. Sixty-five tissue samples from 19 D. marsupialis individuals were negative for Leishmania spp. Conclusions: The presence of the Lutzomyia species that have been identified as vectors for Leishmania inside and around houses in the village of El Bledo, in El Carmen de Bolívar represents a risk of infection. Furthermore, the presence of Lu. panamensis is reported for first time in El Carmen de Bolívar in Colombia. Although the lack of detection of Leishmania spp. in D. marsupialis samples may suggest that D. marsupialis does not play an important role in the transmission cycle of Leishmania in this region, it is necessary to carry out further longitudinal studies to confirm this hypothesis.
Resumen Introducción. El estudio de la interacción entre el parásito, el vector y los huéspedes mamíferos, incluido el hombre, permite entender el comportamiento de la leishmaniasis. Objetivo. Determinar la presencia de especies del género Lutzomyia y detectar la infección por Leishmania spp. en Didelphis marsupialis en un área endémica de leishmaniasis visceral. Materiales y métodos. Se recolectaron flebotomíneos y D. marsupialis con trampas CDC y Tomahawk™, respectivamente. Las especies de Lutzomyia se identificaron usando la clave de Young y Duncan, 1994. Se tomaron biopsias de oreja, cola y muestras de sangre de D. marsupialis para diagnosticar Leishmania spp. mediante la amplificación de un fragmento del gen de la proteína de choque térmico de 70 kD. Resultados. Se identificaron siete especies de Lutzomyia: Lu. evansi, Lu. gomezi, Lu. panamensis, Lu. dubitans, Lu. cayennensis cayennensis, Lu. rangeliana y Lu. trinidadensis. Las tres primeras especies son reconocidas como vectores en el país por estar implicadas en la transmisión de Leishmania spp. En total, 65 muestras de tejidos de oreja, cola y de sangre provenientes de 19 D. marsupialis fueron negativas para Leishmania spp. en la PCR-HSP70. Conclusiones. La presencia de flebotomíneos con importancia epidemiológica en la zona evaluada representa un riesgo de transmisión. Asimismo, Lu. panamensis es reportada por primera vez en El Bledo (Carmen de Bolívar). La ausencia de Leishmania spp. en D. marsupialis podría sugerir que esta especie no tiene un papel importante en el ciclo de transmisión de Leishmania en la vereda El Bledo, por lo que es necesario profundizar en estudios longitudinales para corroborar esta hipótesis.
Subject(s)
Adolescent , Adult , Aged , Animals , Child , Child, Preschool , Female , Humans , Male , Middle Aged , Young Adult , Psychodidae , Disease Reservoirs/parasitology , Didelphis , Insect Vectors , Leishmaniasis, Visceral/epidemiology , Psychodidae/parasitology , Rural Population , Species Specificity , Tail/parasitology , Blood/parasitology , Colombia/epidemiology , HSP70 Heat-Shock Proteins/genetics , Endemic Diseases , Didelphis/parasitology , Ear, External/parasitology , Housing , Insect Vectors/parasitology , Leishmania/isolation & purification , Leishmania/classification , Leishmania/genetics , Leishmaniasis, Visceral/transmissionABSTRACT
Abstract The aim of this study was to compare molecular tests used to diagnose Leishmania spp. in dogs with different stages of infection. Blood and conjunctival swab (CS) samples from dogs classified in four clinical stages were subjected to different PCR protocols (13A/13B, MC1/MC2, LITSR/L5.8S and LEISH-1/LEISH-2 primers). To the study, 22.3% (48/215) of dogs were classified as without clinical signs, 67.5% (145/215) stage I (mild disease), 7.0% (15/215) stage II (moderate disease) and 3.2% (7/215) stage III (severe disease). The results showed that in blood samples, 13A/13B detected a significant higher number of positive dogs in stage I (25/145) and in total (42/215) (p≤0.05). However, when CS samples were tested, no difference was observed (p>0.05). On the other hand, in blood samples, MC1/MC2 detected significantly fewer positive dogs classified as without clinical signs (0/48), in stage I (0/145) and in total (1/215) (p≤0.05). Likewise, in CS samples, this primers showed also lower detection (1/215) (p≤0.05). So than, we can conclude that PCR on blood samples with 13A/13B primers has greater capacity to detect positive dogs, mainly at the initial of clinical disease than do other primers and MC1/MC2 are not a good choice to detect Leishmania infantum infection in dogs.
Resumo O objetivo deste estudo foi comparar testes moleculares usados para diagnosticar Leishmania spp., em cães apresentando diferentes estágios de infecção. Amostras de sangue e suabe conjuntival (SC) de cães classificados em quatro estágios clínicos foram submetidas a diferentes PCRs (primers 13A/13B, MC1/MC2, LITSR/L5.8S e LEISH-1/LEISH-2). Para o estudo, 22,3% (48/215) dos cães foram classificados como sem sinais clínicos, 67,5% (145/215) estágio I (doença leve), 7,0% (15/215) estágio II (doença moderada) e 3,2% (7/215) estágio III (doença grave). Os resultados mostraram que, em amostras de sangue, 13A/13B detectou número significativamente maior de cães positivos no estágio I (25/145) e no total (42/215) (p≤0,05). No entanto, quando as amostras de SC foram testadas, nenhuma diferença foi observada (p>0,05). Por outro lado, no sangue, MC1/MC2 detectou significativamente menos cães positivos sem sinais clínicos (0/48), em estágio I (0/145) e no total (1/215) (p≤0,05). Da mesma forma, em amostras de SC, MC1/MC2 também apresentou menor detecção (1/215) (p≤0,05). Assim, a PCR em amostras de sangue com 13A/13B tem maior capacidade de detectar cães positivos, principalmente no início da doença do que outros primers, e o par de primers MC1/MC2 não é uma boa escolha para detectar infecção por Leishmania infantum em cães.
Subject(s)
Animals , Dogs , Leishmaniasis, Cutaneous/veterinary , Dog Diseases/diagnosis , Leishmaniasis, Visceral/veterinary , Severity of Illness Index , Brazil/epidemiology , DNA, Protozoan/genetics , Leishmaniasis, Cutaneous/diagnosis , Leishmaniasis, Cutaneous/epidemiology , Leishmania infantum/genetics , Dog Diseases/epidemiology , Real-Time Polymerase Chain Reaction/veterinary , Leishmaniasis, Visceral/diagnosis , Leishmaniasis, Visceral/epidemiologyABSTRACT
Abstract INTRODUCTION: Favorable responses in American tegumentary leishmaniasis (ATL) patients to treatment with 5 mg Sbv/kg/day meglumine antimoniate (MA) has been reported in Rio de Janeiro, but little is known regarding the therapeutic response to low doses in patients from other locations. METHODS: A retrospective review of medical records was conducted to compare the therapeutic response to 5 mg Sbv/kg/day MA treatment among 36 patients who acquired ATL in Brazilian states other than Rio de Janeiro (OS group) and 72 patients from Rio de Janeiro (RJ group). RESULTS: One course of 5 mg Sbv/kg/day MA cured 72.8% of 81 cutaneous (CL) and 66.6% of 27 mucosal (ML) leishmaniasis-infected patients: 70% in the CL/RJ group, 81% in the CL/OS group, 50% in the ML/RJ group, and 80% in the ML/OS group. After up to two additional treatment courses at the same dose, 88.9% and 85.2% of the CL and ML patients were cured, respectively. Adverse events were observed in 40% of patients in the CL/RJ group, 57% of the CL/OS group, 58% of the ML/RJ group, and 80% of the ML/OS group. No significant differences were observed in the cure rates or adverse effects between the RJ and OS groups. No patients required permanent discontinuation of treatment due to adverse events. CONCLUSIONS: Patients with ATL acquired in both RJ and OS may respond to low-dose MA. While high-dose MA should remain the standard treatment for ATL, low-dose MA might be preferred when toxicity is a primary concern.
Subject(s)
Humans , Male , Female , Infant, Newborn , Infant , Child, Preschool , Child , Adolescent , Adult , Aged , Aged, 80 and over , Young Adult , Leishmaniasis, Cutaneous/drug therapy , Meglumine Antimoniate/therapeutic use , Antiprotozoal Agents/therapeutic use , Brazil , Retrospective Studies , Treatment Outcome , Leishmaniasis, Cutaneous/pathology , Geography , Middle AgedABSTRACT
A leishmaniose visceral canina é uma zoonose considerada doença tropical de prioridade. A leishmaniose afeta vários sistemas do corpo dos cães, incluindo vísceras e pele. A proteína C reativa (PCR) e o fator reumatoide (FR) são exames realizados na medicina para detecção de inflamação e artrites em seres humanos, no entanto, há poucos trabalhos voltados para cães com leishmaniose que demonstrem as alterações ocorridas na PCR e FR. Este trabalho teve como objetivo demonstrar as alterações de PCR e FR e sua correlação com a hiperproteinemia e hiperalbuminemia, além da compararação com o desvio a esquerda presente no exame hematológico. O trabalho foi realizado no Hospital Veterinário do Centro Universitário da Grande Dourados/MS e Centro de Controle de Zoonoses, no qual foram avaliados 34 cães, de diversar raças e idade e submetidos a colheita de sangue venosa para realização de exames em imuno-látex, bioquímica sérica e hemograma, em cães naturalmente infectados por Leishmania spp. Foram utilizados somente cães positivos ao teste rápido DPP® para leishmaniose, juntamente com resultado positivo no exame parasitológico, depois de diagnosticados foram realizados exames hematológicos e bioquímicos. Quando realizado o teste para quantificação de FR em soro sanguíneo, para os 34 animais estudados, foi observado positividade em apenas 1 animal, enquanto que os cães foram positivos para a PCR em 38,23% dos casos estudados. Em casos de animais com leishmaniose é possível estabelecer níveis inflamatórios precocemente, enquanto que o FR demonstrou não ser um bom marcador para animais soropositivos para a doença.(AU)
Canine visceral leishmaniasis is a zoonosis considered a priority tropical disease. The disease affects various body systems of dogs, including viscera and skin. C-reactive protein (CRP) and rheumatoid factor (RF) are tests performed in medicine for the detection of inflammation and arthritis in humans, however, there are few studies aimed at dogs with leishmaniasis that demonstrate changes in CRP and RF. This work aimed to demonstrate the changes of CRP and RF and its correlation with hyperproteinemia and hyperalbuminemia, in addition to the comparison with the left deviation present in the hematological examination. The work was carried out at the Veterinary Hospital of the University Center of Grande Dourados/MS and Zoonoses Control Center, in which 34 dogs of different breeds and ages were submitted to venous blood collection for immuno-latex exams, Biochemistry and blood count in dogs naturally infected with Leishmania spp. Only dogs to the DPP® rapid test for leishmaniasis were used, together with a positive result in parasitological examination, after hematological and biochemical tests were performed. When the test for the quantification of FR in serum was performed, for the 34 animals studied, positivity was observed in only 1 animal, while the dogs were PCR positive in 38.23% of the cases studied. In cases of animals with leishmaniasis it is possible to establish inflammatory levels early, whereas the FR showed not to be a good marker for animals seropositive for the disease.(AU)
Subject(s)
Animals , Dogs , Rheumatoid Factor/analysis , Protein C/analysis , Dogs/microbiology , Arthritis/veterinary , LeishmaniaABSTRACT
This study aimed to verify the occurrence of Leishmania spp. and Leishmania (Leishmania) infantum in horses from a visceral leishmaniasis endemic area in Brazil. DNA samples from blood and conjunctival swab (CS) were tested by PCR and Indirect Immunofluorescence Antibody Test (IFAT). Although none of the horses was clinically sick, animals infected by Leishmania spp. were found and some could be characterized as infected by L. (L.) infantum. From 40 horses, 100% of the animals were positive by blood PCR, 90% (36/40) by CS PCR, and 2.5% (01/40) in serodiagnosis, by IFAT. Six from these 40 horses were L. (L.) infantum positive by blood PCR. Direct sequencing and analysis of amplicons resulted in a sequence to evolutionary analysis. Results indicate the presence of Leishmania spp. and L. (L.) infantum infecting healthy horses in Brazil. The presence of Leishmania spp. and L. (L.) infantum DNA in asymptomatic horses suggests that they can be important reservoirs of these parasites, a highly relevant finding for the epidemiological surveillance of the diseases they cause.(AU)
O estudo objetivou verificar a ocorrência de Leishmania spp. e Leishmania (Leishmania) infantum em cavalos de uma região endêmica para leishmaniose visceral do Brasil. Amostras de DNA de sangue e suabe conjuntival (SC) foram testadas pela PCR e pela Reação de Imunofluorescência Indireta (RIFI). Embora nenhum cavalo estivesse clinicamente doente, animais infectados por Leishmania spp. e L. (L.) infantum foram encontrados em Ilha Solteira/SP. Dos 40 cavalos, 100% (40/40) foram positivos pela PCR de sangue, 90% (36/40) pela PCR de SC, e 2,5% (01/40) no sorodiagnóstico, pela RIFI. Seis desses 40 cavalos foram positivos para L. (L.) infantum pela PCR de sangue. O sequenciamento direto e a análise dos amplicons resultaram em uma sequência para análise evolutiva. Os resultados indicam a presença de Leishmania spp. e L. (L.) infantum infectando cavalos saudáveis no Brasil. A presença de DNA de Leishmania spp. and L. (L.) infantum em cavalos saudáveis sugere que eles podem ser importantes reservatórios desses parasitas, um achado altamente relevante para a vigilância epidemiológica das doenças que causam.(AU)
Subject(s)
Animals , Serologic Tests/veterinary , Leishmania infantum/immunology , Leishmania/classificationABSTRACT
BACKGROUND Leishmanolysins have been described as important parasite virulence factors because of their roles in the infection of promastigotes and resistance to host's defenses. Leishmania (Viannia) braziliensis contains several leishmanolysin genes in its genome, especially in chromosome 10. However, the functional impact of such diversity is not understood, but may be attributed partially to the lack of structural data for proteins from this parasite. OBJECTIVES This works aims to compare leishmanolysin sequences from L. (V.) braziliensis and to understand how the diversity impacts in their structural and dynamic features. METHODS Leishmanolysin sequences were retrieved from GeneDB. Subsequently, 3D models were built using comparative modeling methods and their dynamical behavior was studied using molecular dynamic simulations. FINDINGS We identified three subgroups of leishmanolysins according to sequence variations. These differences directly affect the electrostatic properties of leishmanolysins and the geometry of their active sites. We identified two levels of structural heterogeneity that might be related to the ability of promastigotes to interact with a broad range of substrates. MAIN CONCLUSION Altogether, the structural plasticity of leishmanolysins may constitute an important evolutionary adaptation rarely explored when considering the virulence of L. (V.) braziliensis parasites.
Subject(s)
Humans , Leishmania braziliensis/genetics , Metalloendopeptidases/genetics , Protein Conformation , Genetic Variation , Models, MolecularABSTRACT
An evaluation was made of the presence of anti-Leishmania infantum chagasi antibodies in domestic dogs from the urban and rural areas of Brazil's Pantanal wetland region using serological techniques. A total of 429 dogs were sampled in three areas of the Pantanal biome, including the municipalities of Poconé, Santo Antônio de Leverger, and Barão de Melgaço, in the state of Mato Grosso, and in the municipality of Corumbá, in the state of Mato Grosso do Sul. The immunofluorescence assay (IFA) was used to detect antibodies (cut-off point 40) using Leishmania infantum chagasi antigen. Because of the possibility of cross-reactivity between species of the genus Leishmania, samples that were positive in the IFA against L. infantum chagasi were also tested by IFA in the same conditions, using L. amazonensis and L. braziliensis antigens. IFA-positive samples to L. infantum chagasi were also evaluated using Enzyme-Linked Immunosorbent Assay (ELISA). The results showed the presence of antibodies against L. infantum chagasi in 23 (5.36%; 95% CI: 3.50%-8.05%) dogs and at least one seroreactive dog was found in each of the municipalities evaluated in this study. Antibody titers ranged from 40 to 5,120, and all IFA positive samples were positive in the ELISA. Among the 23 positive dogs, nine were also were seroreactive for L. amazonensis and L. braziliensis antigens. The occurrence of anti- L. infantum chagasi antibodies in dogs was higher in rural areas (7.06%) than in urban areas (2.50%) (P < 0.05). Based on this study, we concluded that dogs from rural areas of the Pantanal wetlands were in contact with Leishmania species, which is relevant information given their importance to public health.(AU)
Neste trabalho foi realizada uma avaliação sobre a presença de anticorpos anti-Leishmania infantum chagasi em cães domésticos das áreas urbanas e rurais da região do Pantanal brasileiro usando técnicas sorológicas. Um total de 429 cães foram amostrados em três áreas do bioma do Pantanal, incluindo os municípios de Poconé, Santo Antônio de Leverger e Barão de Melgaço, em Mato Grosso, e o município de Corumbá, em Mato Grosso do Sul. A reação de imunofluorescência indireta (RIFI) foi utilizada para detectar anticorpos (ponto de corte de 40) de Leishmania infantum chagasi como antígeno. Devido à possibilidade de reação cruzada entre as espécies do gênero Leishmania, as amostras positivas na RIFI para L. infantum chagasi foram também avaliadas na RIFI utilizando L. amazonensis e L. braziliensis como antígenos. As amostras positivas na RIFI para L. infantum chagasi foram avaliadas utilizando o ensaio de imunoadsorção ligado à enzima (ELISA). Os resultados mostraram a presença de anticorpos contra L. infantum chagasi em 23 (5,36%; IC 95%: 3,50% -8,05%) cães e pelo menos um cão soro-reativo foi encontrado em todos os municípios avaliados neste estudo. Os títulos de anticorpos variaram de 40 a 5.120 e todas as amostras positivas na RIFI foram positivas no ELISA. Entre os 23 cães positivos, nove também reagiram para L. amazonensis e L. braziliensis. A ocorrência de anticorpos anti-L. infantum chagasi em cães foi maior nas áreas rurais (7,06%) do que nas áreas urbanas (2,50%) (P < 0,05). Com base neste estudo, concluímos que cães de áreas rurais do Pantanal tiveram contato com espécies de Leishmania, o que é uma informação relevante, dada a sua importância para a saúde pública.(AU)
Subject(s)
Animals , Dogs , Antibodies, Protozoan/analysis , Leishmania infantum/immunology , Brazil/epidemiology , Enzyme-Linked Immunosorbent Assay/veterinary , Fluorescent Antibody Technique, Indirect/veterinaryABSTRACT
Abstract Leishmaniasis is a major public health problem worldwide. Because Leishmania can adapt to new hosts or vectors, knowledge concerning the current etiological agent in dogs is important in endemic areas. This study aimed to identify the Leishmania species detected in 103 samples of peripheral blood from dogs that were naturally infected with these protozoa. The diagnosis of leishmaniasis was determined through parasitological examination, the indirect enzyme-linked immunosorbent assay (ELISA) and the polymerase chain reaction (PCR). The Leishmania species were identified by means of PCR-restriction fragment length polymorphism (PCR-RFLP). The samples were subjected to PCR using oligonucleotide primers that amplify the intergenic region ITS1 of the rRNA gene in order to identify the species. The amplified DNA was digested using the restriction enzyme HaeIII. A restriction profile identical to L. amazonensis was shown in 77/103 samples and the profile was similar to L. infantum in 17/103. However, a mixed profile was shown in 9/103 samples, which impeded species identification. In conclusion, the infection in these dogs was predominantly due to L. amazonensis, thus indicating that diagnosing of cases of canine leishmaniasis needs to be reexamined, since the causative agent identified is not restricted to L. infantum.
Resumo Leishmaniose é um grande problema de saúde pública global. Devido à adaptação de Leishmania a novos hospedeiros ou vetores, conhecimentos sobre o agente etiológico atual em cães é importante em áreas endêmicas. Este estudo teve como objetivo identificar as espécies de Leishmania detectadas em 103 amostras de sangue periférico de cães naturalmente infectados com este protozoário. O diagnóstico de leishmaniose foi determinado por exame parasitológico, ensaio imunoenzimático (ELISA) e a reação em cadeia da polimerase (PCR). A identificação das espécies de Leishmania foi realizada por PCR – seguido da análise do polimorfismo no comprimento de fragmentos de restrição (PCR-RFLP). As amostras foram submetidas a PCR utilizando-se iniciadores oligonucleotídicos que amplificam a região intergénica ITS1 do gene de rRNA para identificar as espécies, o DNA amplificado foi digerido com a enzima de restrição HaeIII. Observou-se que 77/103 amostras mostraram um perfil de restrição idênticos a L. amazonensis, 17/103 foram semelhantes para L. infantum; 09/103 mostraram um perfil misto, o que impediu a identificação da espécie. Em conclusão, a infecção nestes cães era predominantemente devido a L. amazonensis, indicando que o diagnóstico de casos de leishmaniose canina precisa ser reexaminada, já que o agente causador não está restrito a L. infantum.
Subject(s)
Animals , Dogs , Dog Diseases/parasitology , Leishmaniasis, Visceral/veterinary , Polymorphism, Restriction Fragment Length , Enzyme-Linked Immunosorbent Assay/veterinary , Polymerase Chain Reaction/veterinary , Leishmania infantum/isolation & purification , Leishmania/isolation & purification , Leishmaniasis, Visceral/parasitologyABSTRACT
Abstract INTRODUCTION: Malaria and leishmaniasis are prevalent in tropical regions, which have environmental characteristics that are highly favorable to protozoa and vectors of these diseases; the transmission of these infections in sub-tropical regions, although recognized, represents only a small fraction of cases. Plants are constantly being used in the search for and acquisition of new drugs, and many compounds derived from them have been used to combat various diseases. In this study, we evaluated the action of the dichloromethanolic extract of Myrciaria dubia leaves against the protozoa Plasmodium falciparum, Leishmania amazonensis, Leishmania braziliensis, and Leishmania chagasi through bioassays. METHODS The extract from M. dubia was tested for its anti-P. falciparum activity in an anti-histidine-rich protein II immunosorbent assay. The antileishmanial assays were performed using the resazurin method, while cytotoxicity against human hepatoma (HepG2) strain was determined using the colorimetric MTT [3-(4, 5-dimethyl-2- thiazolyl)-2, 5-diphenyl-2H tetrazolium bromide] method. RESULTS The M. dubia extract presented a half-maximal inhibitory concentration equal to 2.35 (1.05)μg/mL for P. falciparum, 190.73 (6.41) μg/mL for L. amazonensis, and greater than equal to 200µg/mL for L. chagasi and L. braziliensis strains. The cytotoxic concentration for 50% of the cells was above 500μg/mL for HepG2, indicating no toxicity and greater selectivity against parasites. CONCLUSIONS The results obtained indicate the presence of antiplasmodial and leishmanicidal bioactive compounds in the dichloromethanolic extracts of M. dubia leaves, and point towards future studies to elucidate the mechanism of action for each physiological effect.
Subject(s)
Humans , Plasmodium falciparum/drug effects , Plant Extracts/pharmacology , Myrtaceae/chemistry , Leishmania/drug effects , Antimalarials/pharmacology , Antiprotozoal Agents/pharmacology , Plant Extracts/toxicity , Immunoenzyme Techniques , Colorimetry , Inhibitory Concentration 50 , Parasitic Sensitivity Tests , Hep G2 Cells/drug effects , Leishmania/classification , Antimalarials/isolation & purification , Antimalarials/toxicity , Antiprotozoal Agents/isolation & purification , Antiprotozoal Agents/toxicityABSTRACT
Amostras de sangue de 99 cães domiciliados foram coletadas no meio urbano (n = 33) e rural (n = 66) do município de Lábrea, estado do Amazonas, Brasil. Dentre as amostras rurais, 40 foram obtidas em comunidades ribeirinhas e 26 em comunidades indígenas, ambas ao longo do rio Purus. Durante a amostragem foi aplicado um questionário com informações sobre sexo, idade, viver em áreas secas ou alagadiças, acesso ou não às ruas (cães urbanos) e acesso à floresta. A presença de anticorpos contra Toxoplasma gondii, Neospora caninum, Leishmania infantum chagasi e Leishmania amazonensis foi detectada pela reação de imunofluorescência indireta (RIFI) com ponto de corte de, respectivamente, 16, 50, 40 e 40. Associação entre as variáveis qualitativas e a positividade para cada um dos parasitos foi avaliada pelo teste do χ2 (p < 0,05). A ocorrência de animais com anticorpos contra T. gondii, N. caninum e L. amazonensis foi de, respectivamente, 61,6%; 7,1% e 8,1%. Nenhuma amostra foi positiva para L. infantum chagasi. A variável viver em área urbana (p=0,041) apresentou associação com ocorrência de T. gondii e o número de cães positivos a T. gondii aumentou com a idade (p = 0,0006). A variável sexo (machos) apresentou associação com N. caninum (p = 0,018) e nenhuma variável apresentou associação com L. amazonensis. Os títulos de anticorpos contra T. gondii variaram de 64 a 32.768; contra N. caninum de 100 a 800 e contra L. amazonensis de 40 a 640. T. gondii e L. amazonensis são dois agentes de importantes zoonoses e encontram-se ativos na região. O município estudado, especialmente as comunidades ribeirinhas, possuem peculiaridades geográficas, sociais e ecológicas distintas e necessitam maior atenção das autoridades para o controle desses agentes.(AU)
Blood samples from 99 domestic dogs were collected in the urban area (n = 33) and rural area (n = 66) of the municipality of Lábrea, state of Amazonas, Brazil. Among the rural samples, 40 were collected in riverine communities and 26 were collected in Indian communities, both along the Purus River. During the sampling, a questionnaire was applied to obtain information relating to sex, age, living in dryland or seasonally flooded areas, access to the streets (for urban dogs) and access to forests. The presence of antibodies against Toxoplasma gondii, Neospora caninum, Leishmania infantum chagasi and Leishmania amazonensis was detected by means of the indirect fluorescent antibody test (IFAT) with cutoffs of 16, 50, 40 and 40, respectively. The association of each qualitative variable, with each parasite and positivity for each of them, were evaluated using the χ2 test (p < 0.05). T. gondii, N. caninum and L. amazonensis antibodies were found, respectively, in 61.6%, 7.1% and 8.1% of the animals examined. None of the samples were positive for L. infantum chagasi. The variable of living in an urban area (p = 0.041) presented an association with occurrence of T. gondii and the positivity for T. gondii increased with age of the dogs (p = 0.0006). The variable of male sex presented an association with N. caninum (p = 0.018) and no variable presented any association with L. amazonensis. The antibody titers against T. gondii ranged from 64 to 32,768; against N. caninum from 100 to 800; and against L. amazonensis from 40 to 640. Both T. gondii and L. amazonensis are important zoonotic agents and are active in this region. The municipality studied, and especially its riverine communities, has geographic, social and ecological peculiarities. This region requires greater attention from the authorities for controlling these agents.(AU)
Subject(s)
Animals , Dogs , Antibodies/analysis , Leishmania , Neospora , Toxoplasma , Fluorescent Antibody Technique, Indirect/veterinaryABSTRACT
The maned wolf (Chrysocyon brachyurus), an inhabitant of the Brazilian savanna, is considered the largest canid of South America and is classified as a near-threatened species by the International Union for Conservation of Nature (IUNC). The purpose of this study was to investigate the presence of antibodies against Toxoplasma gondii, -Neospora caninum, - Leishmania spp., and -Ehrlichia canis in free-ranging maned wolves in the northeastern region of the state of São Paulo, Brazil. Of the 17 serum samples tested by the indirect fluorescent antibody test (IFAT), 88.2% (15/17), 17.6% (3/17) and 52.9% (9/17) showed anti-T. gondii, -Leishmania spp., and -E. canis antibodies, respectively. None of the studied maned wolves tested positive for N. caninum antibodies. Our results indicated the exposure of free-ranging maned wolves to the agents in question. The presence of industrial complexes, extensive agriculture and habitat fragmentation in the northeastern region of the state of São Paulo puts these wild animals in proximity to urban areas, possibly contributing to the transmission of diseases between wild and domestic animals and human beings.(AU)
O lobo-guará (Chrysocyon brachyurus) habita o ecossistema de Cerrado e é considerado o maior canídeo da América do Sul e uma espécie ameaçada de extinção pela "International Union for Conservation of Nature" (IUNC). O objetivo desse estudo foi investigar a presença de anticorpos anti-Toxoplasma gondii, -Neospora caninum, -Leishmania spp. e -Ehrlichia canis em lobosguará da região nordeste do estado de São Paulo, Brasil. Das 17 amostras de soro testadas por meio da reação de imunofluorescência indireta (RIFI), 88,2% (15/17), 17,6% (3/17) e 52,9% (9/17) apresentaram anticorpos anti-T. gondii, - Leishmania spp. e -E. canis, respectivamente. Todos os animais testados foram soronegativos para N. caninum. Esses resultados indicam a exposição dos lobos-guará dessa região aos agentes pesquisados. A presença de um complexo industrial, agricultura extensiva e fragmentação de habitat na região nordeste do estado de São Paulo, favorece a proximidade desses animais silvestres a ambientes urbanos o que pode contribuir para a transmissão de doenças entre os animais silvestres, domésticos e o homem.(AU)
Subject(s)
Animals , Ehrlichia canis/immunology , Leishmania/immunology , Neospora/immunology , Toxoplasma/immunology , Wolves/virology , Animals, Wild/virology , Fluorescent Antibody Technique, Indirect/veterinaryABSTRACT
Abstract We examined the presence of antibodies against the parasites Toxoplasma gondii, Neospora caninum, and Leishmania spp., as well the presence of DNA from Leishmania spp., in dogs from Pirassununga - SP. The seropositivity rate was compared with the animals’ originating location. Three hundred seventy-three blood samples from the county’s kennel and local veterinary clinics were collected and analyzed. A total of 300 samples were tested for T. gondii and N. caninum using an indirect immunofluorescence antibody test (IFAT); 45% (135/300) were positive for T. gondii and 24.3% (73/300) were positive for N. caninum. Three hundred seventy-three samples were tested for Leishmania spp. using the IFAT. Of these, 4.6% (17/373) were positive. Additionally, 145 samples were tested using a polymerase chain reaction (PCR); of these samples, 0.7% (1/145) was positive. Considering the results, we conclude that these parasites are present in the city of Pirassununga - SP and that the animals have contact with the protozoan. It is therefore necessary to create methods for disease prevention to maintain both animal and human health in regard to leishmaniasis and toxoplasmosis.
Resumo Avaliou-se a presença de anticorpos contra Toxoplasma gondii, Neospora caninum e Leishmania spp.; assim como a presença de DNA de Leishmania spp. em cães de Pirassununga-SP, e associou-se sua soropositividade ao local de origem dos animais. Foram coletadas 373 amostras de sangue do canil municipal e de clínicas veterinárias locais, que foram analisadas pelo teste de Imunofluorescência Indireta (RIFI). Do total, 300 amostras foram testadas para T. gondii e N. caninum, das quais 45% (135/300) foram positivas para T. gondii e 24,3% (73/300) para N. caninum. Para Leishmania spp. foram avaliadas 373 amostras pela RIFI, sendo 4,6% (17/373) positivas. Adicionalmente, 145 amostras foram testadas utilizando-se a PCR e, dessas amostras, 0,7% (1/145) foi positiva. Considerando-se os resultados, pode-se concluir que esses parasitos estão presentes na cidade de Pirassununga - SP e que os animais tiveram contato com os protozoários. Faz-se, dessa forma, necessária a divulgação de meios de prevenção às doenças, com o intuito de manter o controle sobre as mesmas, tanto na saúde animal quanto na saúde humana, em relação à leishmaniose e à toxoplasmose.
Subject(s)
Animals , Toxoplasma/immunology , Antibodies, Protozoan/blood , Neospora/immunology , Dogs/immunology , Leishmania/immunology , Seroepidemiologic Studies , Polymerase Chain Reaction/veterinary , Fluorescent Antibody Technique, Indirect/veterinary , Dogs/parasitologyABSTRACT
The eco-epidemiology of American cutaneous leishmaniasis (ACL) is driven by animal reservoir species that are a source of infection for sand flies that serve as vectors infecting humans with <i>Leishmania</i> spp parasites. The emergence and re-emergence of this disease across Latin America calls for further studies to identify reservoir species associated with enzootic transmission. Here, we present results from a survey of 52 individuals from 13 wild mammal species at endemic sites in Costa Rica and Panama where ACL mammal hosts have not been previously studied. For <i>Leishmania</i> spp. diagnostics we employed a novel PCR technique using blood samples collected on filter paper. We only found <i>Leishmania</i> spp parasites in one host, the two-toed sloth, <i>Choloepus hoffmanni</i>. Our findings add further support to the role of two-toed sloths as an important ACL reservoir in Central America.