Experimental infection by Trypanosoma vivax in goats in the Brazilian semiarid: detection of T. vivax DNA in colostrum and assessment of lactogenic transmission / Infecção experimental por Trypanosoma vivax em caprinos no semiárido brasileiro: detecção de DNA de Trypanosoma vivax no colostro e avaliação da transmissão lactogênica

This study aimed to identify the presence of Trypanosoma vivax DNA in the colostrum of infected goats and to explore the possibility of transmission for neonates fed using colostrum collected from infected goats. We used twelve goats in the final third of gestation with an age of approximately 24 months. Six goats were inoculated intravenously with 0.5mL of blood containing approximately 1.25x105 trypomastigotes of T. vivax, and six remained uninfected. The presence of T. vivax in colostrum was evaluated by Polymerase Chain Reaction (PCR). The possibility of T. vivax transmission by colostrum was assessed by feeding six neonates born of serologically negative goats using colostrum from infected goats. Peripheral blood from neonates was collected daily for thirty days to assess the T. vivax presence through the examination of Giemsa-stained smears of leukocyte layers with the buffy coat technique (BCT) and by PCR. The results of a direct examination of colostrum were negative, but PCR confirmed the presence of T. vivax DNA in all infected goats. Additionally, lactogenic transmission by colostrum was not demonstrated once both BCT and PCR of neonate peripheral blood were negative.

Este estudo teve como objetivo identificar a presença de DNA de Trypanosoma vivax no colostro de cabras infectadas experimentalmente e verificar a possibilidade de transmissão para neonatos alimentados com colostro coletado de cabras infectadas. Foram utilizadas doze cabras no terço final de gestação com idade aproximada de 24 meses. Seis cabras foram inoculadas intravenosamente com 0,5mL de sangue contendo aproximadamente 1,25x105 tripomastigotas de T. vivax, e seis permaneceram não infectadas. A presença de T. vivax no colostro foi avaliada por Reação em Cadeia da Polimerase (PCR). A possibilidade de transmissão de T. vivax pelo colostro foi avaliada através da alimentação de seis neonatos nascidos de cabras sorologicamente negativas com colostro de cabras infectadas. Foi coletado diariamente o sangue periférico dos neonatos, por trinta dias para avaliar a presença de T. vivax através do exame de esfregaços de camadas leucocitárias coradas por giemsa, pela técnica BCT e por PCR. Os resultados do exame direto do colostro foram negativos, mas a PCR confirmou a presença de DNA de T. vivax no colostro em todas as cabras infectadas. Além disso, a transmissão lactogênica pelo colostro não foi demonstrada, uma vez que tanto a BCT quanto a PCR do sangue periférico do neonato foram negativas.

Sp Tripanosomiasis en el ganado: breve revisión de la literatura / En Trypanosomiasis in cattle: brief literature review / Tripanossomose em bovinos: breve revisão de literatura

Teniendo uno de los rebaños comerciales de ganado más grandes del mundo, Brasil se destaca entre otros países, sin embargo, entre los problemas sanitarios que afectan a estos rebaños, la tripanosomosis ha ido ganando espacio y gran trascendencia, debido a los grandes problemas económicos y reproductivos que son que viene provocando en el rebaño brasileño. El agente causal más importante es Trypanosoma vivax, que son protozoos diseminados a través de vectores mecánicos, como tábanos y moscas hematófagas como las del género Stomoxys. Estos agentes se distribuyen por todo el mundo, pero preferentemente en las zonas de clima tropical de Brasil, afectando tanto al ganado lechero como al vacuno, causando grandes daños a los ganaderos. Los signos clínicos de esta enfermedad son inespecíficos, lo que ha suscitado preocupación por la diseminación y falta de diagnóstico de esta enfermedad, pero principalmente incluyen anemia o pérdida progresiva de peso, además de pérdida de productividad en los animales afectados. El diagnóstico se realiza mediante pruebas parasitológicas, como frotis de sangre, pruebas serológicas y moleculares y, principalmente, mediante el método Woo. Finalmente, el tratamiento y control de esta enfermedad consiste en tratamientos de quimioterapia y control de los vectores causantes. En este sentido, esta breve revisión de la literatura tiene como objetivo levantar d

Having one of the largest commercial herds of cattle in the world, Brazil stands out among other countries, however, among the sanitary problems that affect these herds, Trypanosomosis has been gaining space and great significance, due to the major economic and reproductive problems that are coming causing in the brazilian herd. The most important and causative agent is Trypanosoma vivax, which are protozoa disseminated by mechanical vectors, such as horseflies and hematophagous flies such as those of the genus Stomoxys. These agents are distributed all over the world, but preferentially in tropical climate areas in Brazil, affecting both dairy and beef cattle, causing great damage to farmers. The clinical signs of this disease are nonspecific, which has raised concern about the spread and lack of diagnosis of this disease, but mainly include anemia or progressive weight loss, in addition to loss of productivity in affected animals. Diagnosis is made through parasitological tests, such as blood smears, serological and molecular tests, and, mainly, using the Woo method. Finally, the treatment and control of this disease consists of chemotherapy treatments and control of the causative vectors. In this sense, this brief literature review aims to raise data on this disease, such as: etiological agent, clinical signs, epidemiology, diagnosis and treatment, in order to contribute wit

Ao possuir um dos maiores rebanhos comerciais de bovinos do mundo, o Brasil destaca-se entre os demais países, entretanto, dentre os problemas sanitários que acometem esses rebanhos a tripanossomose vem ganhando espaço e grande significância, devido aos grandes problemas econômicos e reprodutivos que vem causando no rebanho brasileiro. O agente de maior importância e causador é o Trypanossoma vivax, que são protozoários disseminados por meio de vetores mecânicos, como tabanídeos e moscas hematófagas como as do gênero Stomoxys. Esses agentes estão distribuídos por todo o mundo, mas preferencialmente em áreas de clima tropicais no Brasil, acometendo tanto bovinos leiteiros quanto bovinos de corte, causando grandes prejuízos aos criadores. Os sinais clínicos desta doença são inespecíficos, o que tem gerado preocupação pela disseminação e falta de diagnóstico dessa enfermidade, mas incluem, principalmente, anemia ou perda progressiva de peso, além de perda da produtividade dos animais acometidos. O diagnóstico é feito por meio de exames parasitológicos, como esfregaços sanguíneos, exames sorológicos e molecular e, principalmente, pelo método de Woo. Por fim o tratamento e controle dessa doença consiste em tratamentos quimioterápicos e controle dos vetores causadores. Neste sentido, esta breve revisão de literatura tem por objetivo levantar dados sobre tal doença, como: agente etiol

Natural infection of Trypanosoma sp. in domestic sheep from Ecuador / Infecção natural do Trypanosoma sp. em ovelhas domésticas do Equador

Trypanosomosis in sheep is a hemoparasitic disease of worldwide interest due to its effects on the health of animals and the economic impact on producers, is caused by the protozoan Trypanosoma sp. In the present study, the occurrence of Trypanosoma sp. in sheep from the urban-rural area of the canton Salitre was determined, through an applied study with a qualitative descriptive prospective cross-sectional approach, carried out between October 1, 2019, and February 19, 2020. Blood samples were extracted from the jugular vein and analyzed by the blood smear method using the Giemsa and Diff-Quick staining techniques. Previously, in a first study realized between 2018 and 2019, 2 cases (2%) of Trypanosoma sp., 1 case of Babesia sp. (1%), and 4 cases of Anaplasma marginale (4%) were identified, but without the presence of symptoms of the disease. However, in this new research study, of 170 animals sampled from 5 herds and aged between 3 and 8 years, 34 (20%) were positive for Trypanosoma sp., 6 for Babesia sp. (3.52%) and 6 for A. marginale (3.52%) with coinfection between them. In this research, deteriorated clinical aspects and low hematological values were also determined in positive animals; besides of the total of positive cases, 25 presented symptoms of hemoparasitic disease, 3 sheep had abortions and 8 died. The results of this study showed that Trypanosoma sp. could already become an endemic parasitosis in sheep in the country, representing a serious problem of animal health.

A tripanossomose em ovinos é uma doença hemoparasitária de interesse mundial devido a seus efeitos sobre a saúde dos animais e o impacto econômico sobre os produtores, Esta doença é causada pelo protozoário Trypanosoma sp. No presente estudo, foi determinada a ocorrência de Trypanosoma sp. em ovelhas da área urbano-rural do Cantão Salitre, através de um estudo aplicado com uma abordagem transversal descritiva qualitativa prospectiva, realizado entre dia primeiro de outubro de 2019, à 19 de fevereiro de 2020. Amostras de sangue foram extraídas da veia jugular e analisadas pelo método de esfregaço de sangue usando as técnicas de coloração Giemsa e Diff-Quick. Anteriormente, em um primeiro estudo realizado entre 2018 e 2019, dois casos (2%) de Trypanosoma sp., foram identificados um caso de Babesia sp. (1%), e quatro casos de Anaplasma marginale (4%), mas sem a presença de sintomas da doença. Entretanto, neste novo estudo de pesquisa, de 170 animais amostrados de cinco rebanhos e com idades entre três e oito anos, 34 (20%) foram positivos para Trypanosoma sp., seis para Babesia sp. (3,52%) e seis para A. marginale (3,52%) com coinfecção entre eles. Nesta pesquisa, aspectos clínicos deteriorados e baixos valores hematológicos também foram determinados em animais positivos; além do total de casos positivos, 25 apresentaram sintomas de doença hemoparasítica, três ovelhas tiveram abortos e oito morreram. Os resultados deste estudo mostram que o Trypanosoma sp. já poderia se tornar uma parasitose endêmica em ovinos no país, representando um grave problema de saúde animal.

Tripanosomíase no rebanho bovino brasileiro ­ Uma breve revisão da literatura / Trypanosomiasis in cattle - Brief literature review / Tripanosomiasis en el ganado - Breve revisión de la literatura

Ao possuir um dos maiores rebanhos comerciais de bovinos do mundo, o Brasil destaca-se entre os demais países, entretanto, dentre os problemas sanitários que acometem esses rebanhos a tripanossomose vem ganhando espaço e grande significância, devido aos grandes problemas econômicos e reprodutivos que vem causando no rebanho brasileiro. O agente de maior importância e causador é o Trypanossoma vivax, que são protozoários disseminados por meio de vetores mecânicos, como tabanídeos e moscas hematófagas como as do gênero Stomoxys. Esses agentes estão distribuídos por todo o mundo, mas preferencialmente em áreas de clima tropicais no Brasil, acometendo tanto bovinos leiteiros quanto bovinos de corte, causando grandes prejuízos aos criadores. Os sinais clínicos desta doença são inespecíficos, o que tem gerado preocupação pela disseminação e falta de diagnóstico dessa enfermidade, mas incluem, principalmente, anemia ou perda progressiva de peso, além de perda da produtividade dos animais acometidos. O diagnóstico é feito por meio de exames parasitológicos, como esfregaços sanguíneos, exames sorológicos e molecular e, principalmente, pelo método de Woo. Por fim o tratamento e controle dessa doença consiste em tratamentos quimioterápicos e controle dos vetores causadores. Neste sentido, esta breve revisão de literatura tem por objetivo levantar dados sobre tal doença, como: agente etiológico, sinais clínicos, epidemiologia, diagnóstico e tratamento, a fim de contribuir com informações sobre a enfermidade que está ganhando espaço e necessita de maior disseminação de conhecimentos, para que não seja esquecida e subdiagnosticada.(AU)

Having one of the largest commercial herds of cattle in the world, Brazil stands out among other countries, however, among the sanitary problems that affect these herds, Trypanosomosis has been gaining space and great significance, due to the major economic and reproductive problems that are coming causing in the brazilian herd. The most important and causative agent is Trypanosoma vivax, which are protozoa disseminated by mechanical vectors, such as horseflies and hematophagous flies such as those of the genus Stomoxys. These agents are distributed all over the world, but preferentially in tropical climate areas in Brazil, affecting both dairy and beef cattle, causing great damage to farmers. The clinical signs of this disease are nonspecific, which has raised concern about the spread and lack of diagnosis of this disease, but mainly include anemia or progressive weight loss, in addition to loss of productivity in affected animals. Diagnosis is made through parasitological tests, such as blood smears, serological and molecular tests, and, mainly, using the Woo method. Finally, the treatment and control of this disease consists of chemotherapy treatments and control of the causative vectors. In this sense, this brief literature review aims to raise data on this disease, such as: etiological agent, clinical signs, epidemiology, diagnosis and treatment, in order to contribute with information about the disease that is gaining ground and needs further dissemination of knowledge, so that it is not forgotten and underdiagnosed.(AU)

Teniendo uno de los rebaños comerciales de ganado más grandes del mundo, Brasil se destaca entre otros países, sin embargo, entre los problemas sanitarios que afectan a estos rebaños, la tripanosomosis ha ido ganando espacio y gran trascendencia, debido a los grandes problemas económicos y reproductivos que son que viene provocando en el rebaño brasileño. El agente causal más importante es Trypanosoma vivax, que son protozoos diseminados a través de vectores mecánicos, como tábanos y moscas hematófagas como las del género Stomoxys. Estos agentes se distribuyen por todo el mundo, pero preferentemente en las zonas de clima tropical de Brasil, afectando tanto al ganado lechero como al vacuno, causando grandes daños a los ganaderos. Los signos clínicos de esta enfermedad son inespecíficos, lo que ha suscitado preocupación por la diseminación y falta de diagnóstico de esta enfermedad, pero principalmente incluyen anemia o pérdida progresiva de peso, además de pérdida de productividad en los animales afectados. El diagnóstico se realiza mediante pruebas parasitológicas, como frotis de sangre, pruebas serológicas y moleculares y, principalmente, mediante el método Woo. Finalmente, el tratamiento y control de esta enfermedad consiste en tratamientos de quimioterapia y control de los vectores causantes. En este sentido, esta breve revisión de la literatura tiene como objetivo levantar datos sobre esta enfermedad, tales como: agente etiológico, signos clínicos, epidemiología, diagnóstico y tratamiento, con el fin de aportar información sobre la enfermedad que está ganando terreno y necesita una mayor difusión del conocimiento. para que no sea olvidado e infradiagnosticado.(AU)

Follow-up of dairy cattle naturally infected by Trypanosoma vivax after treatment with isometamidium chloride / Acompanhamento de bovinos leiteiros naturalmente infectados com Trypanosoma vivax após tratamento com cloreto de isometamidium

Trypanosoma vivax infections cause nonspecific clinical signs in cattle associated with aparasitemic intervals, making disease diagnosis a challenge. In Brazil, diminazene aceturate and isometamidium chloride (ISM) are available to treat bovine trypanosomosis. The objective of this study was to follow-up, by molecular and serological techniques, dairy cattle naturally infected by T. vivax after ISM treatment. Thirty cattle naturally infected with T. vivax received two applications of ISM, at a dosage of 1.0 mg/kg intramuscularly, on days 0 and 150. For T. vivax diagnosis, EDTA-blood and serum samples were evaluated on 0, 7, 15, 30, 60, 90, 120, 150, 180, 210, and 240 days after treatment PCR, Loop-mediated isothermal amplification (LAMP) and ELISA. Animals with persistent detection of T. vivax DNA by both PCR and LAMP were found and continuous detection of anti-T. vivax IgG antibodies by ELISA, suggesting the presence of T. vivax resistance to ISM. The combination of LAMP and ELISA tests can prevent misdiagnosis of the parasite clearance in treated cattle, contributing to better disease control. This is the first experiment that demonstrates the persistence infection of T. vivax under ISM treatment in a natural infected herd and evidence of ISM chemotherapy-resistant T. vivax in Brazil.(AU)

Em bovinos, infecções por Trypanosoma vivax geram sinais clínicos inespecíficos que, associados a intervalos aparasitêmicos, faz com que o diagnóstico da enfermidade seja desafiador. No Brasil, somente aceturato de diaminazeno e cloridrato de isometamidum (ISM) estão disponíveis para o tratamento da tripanossomose bovina. Este trabalho teve como objetivo acompanhar bovinos leiteiros naturalmente infectados por T. vivax, após o tratamento com ISM por meio de técnicas moleculares e sorológica. Foram utilizados 30 bovinos naturalmente infectados com T. vivax, sendo estes tratados com duas aplicações de ISM, na dosagem de 1,0 mg/kg por via intramuscular profunda, nos dias 0 e 150. Foram avaliadas, para diagnóstico de T. vivax, amostras de sangue acrescido de EDTA e soro, colhidas nos 0, 7, 15, 30, 60, 90, 120, 150, 180, 210 e 240 dias após os tratamentos pela reação em cadeia da polimerase (PCR), amplificação circular isotérmica do DNA (LAMP) e ensaio de imunoabsorção enzimático (ELISA). Verificou-se a presença de animais com persistência na detecção de DNA de T. vivax pela PCR e LAMP, bem como detecção contínua de anticorpos IgG anti-T. vivax pelo método de ELISA, sugerindo a presença de resistência de T. vivax ao ISM. A combinação dos testes LAMP e ELISA pode evitar falsos diagnósticos da eliminação do parasita nos bovinos tratados, contribuindo para um melhor controle da doença. Este é o primeiro experimento que demonstra infecção persistente do T. vivax em rebanho naturalmente infectado, tratado com ISM, e evidencia possível resistência ao quimioterápico no Brasil.(AU)

Comparison of conventional and molecular techniques for Trypanosoma vivax diagnosis in experimentally infected cattle / Comparação de técnicas convencionais e moleculares para diagnóstico em bovinos experimentalmente infectados por Trypanosoma vivax

Livestock infections by Trypanosoma vivax have been occurring with increasing frequency, mainly due to the presence of animals with subclinical infections and without apparent parasitaemia, making diagnosis challenging. The aim of the present study was to evaluate several techniques used for T. vivax diagnosis in order to assess the best way of using them during the course of the disease. Molecular methods demonstrated higher rates of detection than parasitological methods, detecting 33 of the 54 (61.1%) known positive samples, while the hematocrit centrifugation technique (best parasitological test) detected only 44.4%. The serological methods, IFAT and ELISA, detected seropositivity in 51 of the 54 (94.4%) and 49 of the 54 (90.7%) known positive samples, respectively. Despite being highly sensitive, the latter only demonstrates exposure to the infectious agent and does not indicate whether the infection is active. The present study was the first to use the qPCR for a South American isolate, improving disease detection and quantification. Furthermore, the analyses revealed that the patent phase of the disease may extend up to 42 days, longer than previously reported. The combination of several diagnostic techniques can lower the frequency of false negative results and contributes toward better disease control.(AU)

Infecções por Trypanosoma vivax têm ocorrido com frequência crescente em animais de produção, principalmente pela aquisição de animais com infecções subclínicas e sem aparente parasitemia, o que dificulta o diagnóstico. O objetivo do presente estudo foi avaliar várias técnicas empregadas para o diagnóstico de T. vivax, a fim de verificar a melhor maneira de utilizá-las durante o curso da doença. Os métodos moleculares demonstraram maiores taxas de detecção que os métodos parasitológicos, detectando 33 das 54 (61,1%) amostras sabidamente positivas, enquanto a técnica de hemoconcentração (melhor teste parasitológico) detectou apenas 44,4%. Os métodos sorológicos, RIFI e ELISA, detectaram soropositividade em 51 das 54 (94,4%) e 49 das 54 (90,7%) amostras sabidamente positivas, respectivamente. Apesar de serem altamente sensíveis, estes testes apenas demonstram a exposição ao agente infeccioso, e não indicam se a infecção permanece ativa. O presente estudo foi o primeiro a utilizar a qPCR para um isolado sul-americano, melhorando sua detecção e quantificação. Além disso, as análises revelaram que a fase patente da doença pode se estender por até 42 dias após a infecção, sendo maior que anteriormente relatado. A combinação de várias técnicas de diagnóstico pode evitar a frequência de resultados falso-negativos e contribuir para um melhor controle da doença.(AU)

Risk factors for trypanosomiasis by Trypanosoma vivax in cattle raised in Rio Grande do Norte state / Fatores de risco para tripanossomose por Trypanosoma vivax em bovinos criados no estado do Rio Grande do Norte

The objective of this study was to determine the prevalence of anti Trypanosoma vivax antibodies and the possible risk factors associated with the infection in cattle in Rio Grande do Norte, Northeastern Brazil, through a cross-sectional epidemiological study, with non-probabilistic convenience sampling. A total of 467 cattle's serum samples were analyzed by indirect immunofluorescence. Forty-two samples tested positive for Trypanosoma vivax IgG antibodies, corresponding to the prevalence of 9%. Risk factors influencing the occurrence of trypanosomiasis were milk exploration, raising of European breeds, productivity category: lactation cow, purchase of new cattle, foraging habits near ponds and rivers, and the presence of mechanical vectors. So, high prevalence in beef animals (59.5%), females (95.2%), European breed (88.1%), lactating cows (85.7%), pasture at banks of dams and rivers (95.2%), in addition to the presence of mechanical vectors (81%) and acquisition of animals (88.1%), indicates the expansion of trypanosomiasis in Northeastern semi-arid region, and the information obtained may explain the epidemiological factors that determine the occurrence of trypanosomiasis by T. vivax in this region.(AU)

Objetivando determinar a prevalência de anticorpos anti-Trypanosoma vivax e os possíveis fatores de risco associados à infecção em bovinos no estado do Rio Grande do Norte, nordeste do Brasil, o trabalho consistiu em um estudo epidemiológico transversal, com amostragem não probabilística por conveniência, no qual foram analisadas, por meio da reação de imunofluorescência indireta, 467 amostras de soro sanguíneo de bovinos. Das amostras testadas, 42 foram reagentes para anticorpos IgG anti-Trypanosoma vivax, o que correspondeu à prevalência de 9,0%. Os fatores de risco que influenciaram a ocorrência da tripanossomose foram: exploração com finalidade do tipo leite, criação de bovinos de raça europeia, categoria animal vaca em lactação, aquisição de animais, forrageamento das margens de açudes e rios, além da presença de vetores mecânicos. A alta prevalência encontrada em animais de corte (59,5%), fêmeas (95,2%), raça europeia (88,1%), vacas em lactação (85,7%), pastagem a margens de açudes e rios (95,2%), além da presença de vetores mecânicos (81%) e aquisição de animais (88,1%), indica a expansão da tripanossomose no semiárido do Nordeste, e as informações obtidas poderão esclarecer os fatores epidemiológicos que determinam a ocorrência da tripanossomose por T. vivax na região.(AU)

Risk factors for trypanosomiasis by Trypanosoma vivax in cattle raised in Rio Grande do Norte state / Fatores de risco para tripanossomose por Trypanosoma vivax em bovinos criados no estado do Rio Grande do Norte

The objective of this study was to determine the prevalence of anti Trypanosoma vivax antibodies and the possible risk factors associated with the infection in cattle in Rio Grande do Norte, Northeastern Brazil, through a cross-sectional epidemiological study, with non-probabilistic convenience sampling. A total of 467 cattle's serum samples were analyzed by indirect immunofluorescence. Forty-two samples tested positive for Trypanosoma vivax IgG antibodies, corresponding to the prevalence of 9%. Risk factors influencing the occurrence of trypanosomiasis were milk exploration, raising of European breeds, productivity category: lactation cow, purchase of new cattle, foraging habits near ponds and rivers, and the presence of mechanical vectors. So, high prevalence in beef animals (59.5%), females (95.2%), European breed (88.1%), lactating cows (85.7%), pasture at banks of dams and rivers (95.2%), in addition to the presence of mechanical vectors (81%) and acquisition of animals (88.1%), indicates the expansion of trypanosomiasis in Northeastern semi-arid region, and the information obtained may explain the epidemiological factors that determine the occurrence of trypanosomiasis by T. vivax in this region.(AU)

Objetivando determinar a prevalência de anticorpos anti-Trypanosoma vivax e os possíveis fatores de risco associados à infecção em bovinos no estado do Rio Grande do Norte, nordeste do Brasil, o trabalho consistiu em um estudo epidemiológico transversal, com amostragem não probabilística por conveniência, no qual foram analisadas, por meio da reação de imunofluorescência indireta, 467 amostras de soro sanguíneo de bovinos. Das amostras testadas, 42 foram reagentes para anticorpos IgG anti-Trypanosoma vivax, o que correspondeu à prevalência de 9,0%. Os fatores de risco que influenciaram a ocorrência da tripanossomose foram: exploração com finalidade do tipo leite, criação de bovinos de raça europeia, categoria animal vaca em lactação, aquisição de animais, forrageamento das margens de açudes e rios, além da presença de vetores mecânicos. A alta prevalência encontrada em animais de corte (59,5%), fêmeas (95,2%), raça europeia (88,1%), vacas em lactação (85,7%), pastagem a margens de açudes e rios (95,2%), além da presença de vetores mecânicos (81%) e aquisição de animais (88,1%), indica a expansão da tripanossomose no semiárido do Nordeste, e as informações obtidas poderão esclarecer os fatores epidemiológicos que determinam a ocorrência da tripanossomose por T. vivax na região.(AU)

PARÂMETROS EPIDEMIOLÓGICOS PARA A FORMULAÇÃO DE UM MODELO MATEMÁTICO DA TRIPANOSOMOSE BOVINA

A infecção por Trypanosoma vivax em bovinos promove impactos socioeconômicos nas Américas, África e Ásia. Nas Américas, sua transmissão ocorre de forma mecânica, com intermediação de vetores hematófagos e de fômites. Alguns fatores epidemiológicos facilitam a dispersão do T. vivax entre áreas endêmicas e indenes, tais como: dificuldade na identificação de animais infectados devido às limitações dos métodos diagnósticos, variações na forma de apresentação da doença. Apesar desses fatores facilitarem o ingresso da enfermidade em zonas indenes, a contribuição de suas interações para a dinâmica epidemiológica da enfermidade incluindo os atributos da tríade epidemiológica (vetores, ambiente e hospedeiro) ainda é pouco compreendida. Com base na carência de informações, este trabalho visou a compilação de estimativas de parâmetros epidemiológicos relevantes à dinâmica da doença nas Américas. Publicações científicas (i.e., artigos, dissertações, teses e livros) que envolvessem a estimativa de parâmetros epidemiológicos da tripanossomose bovina foram buscados em bases de dados online. Selecionou-se 41 publicações que descrevessem a interação entre T. vivax e vetores, assim como hospedeiro. Com base nas estimativas de parâmetros, foi proposto um modelo matemático para a dinâmica da tripanossomose que inclui como hospedeiro os bovinos (entre as fases suscetíveis, latente, infectado e recuperado) e a transmissão envolvendo três vetores hematófagos e o compartilhamento de fômite entre os indivíduos. Com base na dinâmica, foi modelado que a interação entre indivíduos infectados possui diferença na participação da transmissibilidade, com isto foi proposto a categorização da fase entre infectados agudo A1, A2, crônicos C1 e C2. As perspectivas futuras deste trabalho se devem a promoção dos parâmetros epidemiológicos na formulação de modelo matemático específico à transmissão mecânica que ocorre nas Américas. Nisto, este trabalho também se trata do primeiro modelo matemático da tripanossomose bovina nas Américas.

Infection by Trypanosoma vivax in cattle promotes socioeconomic impacts in the Americas, Africa and Asia. In the Americas, its transmission occurs mechanically, with the intermediation of hematophagous and fomite vectors. Some epidemiological factors facilitate the spread of T. vivax between endemic and unaffected areas, such as: difficulty in identifying infected animals due to limitations in diagnostic methods, variations in the presentation of the disease. Although these factors facilitate the entry of the disease into free areas, the contribution of their interactions to the disease's epidemiological dynamics, including the attributes of the epidemiological triad (vectors, environment and host) is still poorly understood. Based on the lack of information, this work aimed to compile estimates of epidemiological parameters relevant to the dynamics of the disease in the Americas. Scientific publications (i.e., articles, dissertations, theses and books) involving the estimation of epidemiological parameters of bovine trypanosomosis were searched in online databases. We selected 41 publications describing the interaction between T. vivax and vectors, as well as the host. Based on the parameter estimates, a mathematical model for the dynamics of trypanosomosis was proposed, which includes cattle as a host (between the susceptible, latent, infected and recovered phases) and transmission involving three hematophagous vectors and the sharing of fomite between individuals. Based on the dynamics, it was modeled that the interaction between infected individuals has a difference in the participation of transmissibility, with this it was proposed the categorization of the phase between acutely infected A1, A2, chronic C1 and C2. The future perspectives of this work are due to the promotion of epidemiological parameters in the formulation of a specific mathematical model for the mechanical transmission that occurs in the Americas. In this, this work is also the first mathematical model of bovine trypanosomosis in the Americas.

AUSÊNCIA DE ANTICORPOS EM EQUÍDEOS EXPOSTOS A REBANHOS BOVINOS INFECTADOS POR Trypanosoma vivax

Trypanosoma vivax é hemoprotozoário que acomete especialmente os animais ungulados silvestres e domésticos. Diversos relatos comprovam a ocorrência deste parasita em equídeos na África, sendo os equinos mais susceptíveis que os asininos. Entretanto, o Brasil, mesmo sendo endêmico para a doença em bovinos, existem raros diagnósticos de T. vivax em equídeos. Esse trabalho objetivou verificar a presença de anticorpos anti-T. vivax em equídeos em contato direto com rebanhos bovinos positivos para T. vivax nos estados de MG, SP e CE. Foram testados 154 equídeos para T. vivax através do método de RIFI. Dentre esses, 32 animais apresentaram alterações clínica, como: ataxia, lesões hepáticas e distúrbios reprodutivos. Esses equídeos sintomáticos também foram submetidos a sorologia para T. gondii, N. caninum, T. evansi, T. equi e B. caballi, sendo T. gondii o agente de maior ocorrência. A ausência de resultados positivos para T. vivax indica que equídeos possam ser refratários a esse agente representando uma importância questionável na cadeia epidemiológica da tripanossomose bovina no Brasil.

Trypanosoma vivax is a hemoprotozoan that especially infects wild and domestic ungulate animals. Several reports prove this parasite's occurrence in equids in Africa, but horses more susceptible than donkeys. Although Brazil is endemic for T. vivax cattle disease, there are rare T. vivax diagnoses in equidea. This study aimed to verify the presence of anti-T vivax antibodies in equines living in direct contact with cattle T. vivax positive in MG, SP and CE states. 154 horses were tested for T. vivax using RIFI method. Among these, 32 animals were symptoms, such as: ataxia, liver injury and reproductive disorders. These symptomatic equidae were also subjected to serology exams for T. gondii, N. caninum, T. evansi, T. equi and B. caballi, and T. gondii had been the most frequent agent. The absence of T. vivax positive results indicates equidae may be refractory to this agent, representing a questionable importance in epidemiology bovine trypanosomiasis in Brazil.

ASPECTOS CLÍNICO-EPIDEMIOLÓGICOS E TRATAMENTO DA TRIPANOSOMOSE BOVINA POR Trypanosoma vivax NO ESTADO DE GOIÁS

Trypanosoma (Duttonella) vivax é o protozoário causador da tripanosomose bovina. Uma hemoparasitose de ruminantes que vem assumindo grande importância econômica no Brasil. Sua transmissão pode ocorrer por vetores e também pela via iatrogênica. Animais infectados apresentam sinais clínicos comuns a diversas outras doenças, o que dificulta o diagnóstico e tratamento precoce em rebanhos infectados. Nos últimos 10 anos, a doença vem constantemente se expandindo para novos territórios brasileiro. Este estudo relata o primeiro caso de tripanosomose bovina causada por Trypanosoma vivax no estado de Goiás, bem como outros casos que ocorreram dentro de um período de 24 meses, demonstrando aspectos epidemiológicos, como o compartilhamento de agulhas e a comercialização de vacas infectadas, que influenciaram na dispersão da doença. Ainda, observou-se que T. vivax foi capaz de infectar e desenvolver a doença em bezerros, independente se inoculados pela via intradérmica, subcutânea, intramuscular ou endovenosa. A presença de Anaplasma marginale latente nos bezerros com tripanosomose interferiu diretamente no percentual de mortalidade dos animais. Por fim, com relação à eficácia, apenas animais que receberam isometamidium foram capazes de permanecer sem nova parasitemia durante os 180 dias de estudo. Animais que receberam diminazene apresentaram nova parasitemia quando reinfectados 50 dias após o tratamento e, por ultimo, imidocarb não foi eficaz no tratamento da tripanosomose bovina. Este é o primeiro trabalho que descreve a presença de T. vivax, bem como sua epidemiologia no estado de Goiás, avaliou-se a capacidade de infecção deste parasito por diferentes vias, os sinais clínicos, métodos de diagnóstico e, também, avaliou-se a eficácia do tratamento com imidocarb, diminazene e isometamidium em bovinos experimentalmente infectados com T. vivax no Brasil.

Trypanosoma (Duttonella) vivax is the protozoan that causes bovine trypanosomiasis. A hemoparasitosis of ruminants that has been assuming great economic importance in Brazil. Its transmission can occur by vectors and also by the iatrogenic way. Infected animals show clinical signs common to several other diseases, which makes it difficult to diagnose and treat early in infected herds. In the last 10 years, the disease has been constantly expanding to new Brazilian territories. This study reports the first case of bovine trypanosomiasis caused by Trypanosoma vivax in Goiás, Brazil, as well as other cases that occurred within a period of 24 months, demonstrating epidemiological aspects such as needle sharing and commercialization of infected cows influencing the spread of this disease. Furthermore, it was observed that T. vivax was able to infect and develop the disease in calves when they were inoculated by intradermal, subcutaneous, intramuscular or intravenous way. The presence of Anaplasma marginale latent, in calves with trypanosomiasis, interfer directly in the percentage of mortality of the animals. Finally, with regard to efficacy, only animals that received isometamidium were able to remain without new parasitaemia after 180 days of study. Treatment with diminazene allowed new parasitemia when reinfected 50 days after treatment and, finally, imidocarb was not effective in the treatment of bovine trypanosomosis. This is the first study that describes the presence of T. vivax, as well as its epidemiology in the State of Goiás, evaluated the infection capacity of this parasite by different pathways, clinical signs, and diagnostic methods and also evaluated the efficacy of the treatment with imidocarb, diminazene and isometamidium in cattle experimentally infected with T. vivax in Brazil.

Susceptibility of Trypanosoma evansi in the copaiba oil: in vitro test and in mice experimentally infected with the parasite / Susceptibility of Trypanosoma evansi in the copaiba oil: in vitro test and in mice experimentally infected with the parasite

Background: Trypanosoma evansi is a flagellate which belongs to the salivate section, commonly observed parasitizing blood of equines, ruminants, pigs, dogs and wild animals in different regions of the world. It causes many losses to farmers due to death of animals and drug spending in endemic areas. The treatment of this disease in Brazil is only performed with diminazene aceturate; however it has been ineffective for many animals. During the lats years many studies have been carried out with natural products such as the essential oils. Copaiba oil stands out due some properties described as anti-inflammatory, healing, antiedematogenic, antitumor, parasitic and antibacterial. Therefore, this study aimed to test, in vitro and in vivo, the susceptibility of T. evansi to copaiba oil. Materials, Methods & Results: The oils used in this study were obtained from Copaifera reticulata and Copaifera duckei trees, commonly found in the Tapajos National Forest. The procedure received authorization of IBAMA due the scientific purposes. This study identified three oils identified as copaiba 4-C (C. reticulata), copaiba 5-C (C. duckei) and copaiba 8-C (C. reticulata). The bioassay was performed in vitro using specific culture medium for T. evansi, previously described by Baltz, 1985. Copaiba oil was dissolved in dimethyl sulfoxide (DMSO) and tested in three concentrations (0.5, 1.0 and

Background: Trypanosoma evansi is a flagellate which belongs to the salivate section, commonly observed parasitizing blood of equines, ruminants, pigs, dogs and wild animals in different regions of the world. It causes many losses to farmers due to death of animals and drug spending in endemic areas. The treatment of this disease in Brazil is only performed with diminazene aceturate; however it has been ineffective for many animals. During the lats years many studies have been carried out with natural products such as the essential oils. Copaiba oil stands out due some properties described as anti-inflammatory, healing, antiedematogenic, antitumor, parasitic and antibacterial. Therefore, this study aimed to test, in vitro and in vivo, the susceptibility of T. evansi to copaiba oil. Materials, Methods & Results: The oils used in this study were obtained from Copaifera reticulata and Copaifera duckei trees, commonly found in the Tapajos National Forest. The procedure received authorization of IBAMA due the scientific purposes. This study identified three oils identified as copaiba 4-C (C. reticulata), copaiba 5-C (C. duckei) and copaiba 8-C (C. reticulata). The bioassay was performed in vitro using specific culture medium for T. evansi, previously described by Baltz, 1985. Copaiba oil was dissolved in dimethyl sulfoxide (DMSO) and tested in three concentrations (0.5, 1.0 and

ESTUDOS PRELIMINARES NA IDENTIFICAÇÃO DE BIOMARCADORES NO SORO DE CAMUNDONGOS INFECTADOS EXPERIMENTALMENTE POR Trypanosoma evansi

CALOMENO, Nathália Anderson. Estudos preliminares na identificação de biomarcadores no soro de camundongos infectados experimentalmente por Trypanosoma evansi. 2018. 106 p. Dissertação (Mestrado) - Universidade do Estado de Santa Catarina, Centro de Ciências Agroveterinárias, Mestrado em Ciência Animal, Lages, 2018. O Trypanosoma evansi é o agente causador do "mal das cadeiras" ou surra, uma tripanossomose responsável por perdas na equinocultura e consequentemente no manejo pecuário no Brasil. O diagnóstico diferencial das tripanossomoses é essencial para a tomada de medidas preventivas e curativas da doença. Recentemente, o uso de biomarcadores, como as proteínas do sangue, tem se tornado uma ferramenta poderosa para a detecção de um estado ou condição biológica, através da análise de tecidos ou fluídos biológicos. No entanto, a caracterização de proteínas como novos biomarcadores é um desafio uma vez que as proteínas plasmáticas mais abundantes representam 95% da proteína total na amostra, mascarando as proteínas de interesse com menor densidade e assim dificultando a análise. O uso de métodos de depleção de proteínas é atualmente uma alternativa que permite a remoção de proteínas plasmáticas de alta e média abundância, proporcionando o acesso às proteínas de baixa abundância para estudos de proteômica. A presente pesquisa teve como objetivo identificar biomarcadores proteicos na circulação sanguínea da infecção aguda pelo T. evansi em camundongos. A metodologia foi focada na utilização de um kit comercial de depleção baseado em troca iônica. As proteínas de baixa abundância recuperadas foram analisadas por eletroforese em gel de poliacrilamida com a subsequente identificação dos peptídeos por espectrometria de massa. A partir de um único animal infectado foram identificadas sete proteínas de T. evansi. Com análises de bioinformática, foi possível predizer que todas estão localizadas no citoplasma e/ou núcleo celular do tripanossomatídeo. Quatro delas (alfa e beta tubulina, piruvato quinase e HSP83) já foram identificadas como proteínas secretadas por microvesículas em tripanossomatídeos. Algumas já foram citadas na literatura por se mostrarem imunogênicas e nossos dados sugerem que todas podem ser possíveis biomarcadores da infecção deste parasita. Porém, ainda se faz necessário a repetição do experimento com um número maior de animais e réplicas triplicatas biológicas e experimentais para posteriormente validação dos biomarcadores e desenvolvimento de um teste de diagnóstico sensível e específico da infecção por T. evansi.

CALOMENO, Nathália Anderson. Preliminary studies on the identification of biomarkers in the serum of mice experimentally infected by Trypanosoma evansi. 2018. 106 p. Dissertation (Master) State University of Santa Catarina, Agroveterinary Science Center, Master in Animal Science, Lages, 2018. Trypanosoma evansi is the agent of "surra", a trypanosomosis responsible for losses in the echinoculture and consequently in cattle management in Brazil. The differential diagnosis of trypanosomes is essential for preventive and curative measures of the disease. Recently, the use of biomarkers, such as blood proteins, has become a powerful tool for the detection of a biological condition or state, through the analysis of biological tissues or fluids. However, the characterization of proteins as new biomarkers is a challenge since the most abundant plasma proteins represent 95% of the total protein in the sample, masking the proteins of interest with lower density and thus making the analysis difficult. The use of protein depletion methods is currently an alternative that allows the removal of high and medium abundance plasma proteins, providing access to proteins of low abundance for proteomics studies. The present work aimed to identify protein biomarkers in the bloodstream of acute T. evansi infection in mice. The methodology was focused on the use of a commercial depletion kit based on ion exchange. The low abundance proteins recovered were analyzed by polyacrylamide gel electrophoresis with subsequent identification of the peptides by mass spectrometry. Seven T. evansi proteins were identified from a single infected animal. With bioinformatics analyzes, it has been possible to predict that all are located in the cytoplasm and/or T. evansicell nucleus. Four of them (alpha and beta tubulin, pyruvate kinase and HSP83) have already been identified as proteins secreted by microvesicles in trypanosomatids. Some have already been cited in the literature for being immunogenic and our data suggest that all may be possible biomarkers of the infection of this parasit. However, it is still necessary to repeat the experiment with more animals and biological and experimental triplicates to later validate the biomarkers and develop a sensitive and specific diagnostic test for T. evansi infection.

TRIAGEM E IDENTIFICAÇÃO DE COMPOSTOS PRESENTES NO PATHOGEN BOX® COM ATIVIDADE ANTI-Trypanosoma evansi

CANEVER, M. F. Triagem e Identificação de Compostos Presentes no Pathogen Box® com Atividade Anti-Trypanosoma evansi. 2018. Dissertação (Mestrado em Ciência Animal) - Universidade do Estado de Santa Catarina, Lages, 2018. O parasita Trypanosoma evansi, agente etiológico da surra, possui distribuição cosmopolita e apesar de ser descrito inicialmente como causador da doença em equinos, já existem relatos da infecção em inúmeras espécies domésticas e selvagens (cães, camelos, bovinos, caprinos, capivara, morcegos hematófagos, entre outros). Atualmente o tratamento e profilaxia da doença causada por T. evansi são baseados na administração de fármacos como suramina, aceturato de diminazeno, melarsomina e isometamidium. As principais limitações encontradas no uso desses fármacos estão associadas à toxicidade em algumas espécies, e relatos de cepas resistentes ao tratamento. Com o intuito de encontrar novas alternativas para tratamento de doenças negligenciadas, a Medicines for Malaria Venture desenvolveu o Pathogen Box® - um conjunto de placas contendo quatrocentos compostos distribuídos individualmente em poços. O objetivo deste trabalho foi avaliar a atividade anti-T. evansi de compostos presentes no Pathogen Box® e identificar moléculas que poderão ser utilizadas futuramente no desenvolvimento de novos fármacos para tratamento e profilaxia da surra. Dentre os quatrocentos compostos analisados, sete (pentamidina, MMV688410, MMV687273, MMV022478, MMV688763, MMV676602 e auranofina) apresentaram atividade potencial contra T. evansi reduzindo o número de células em cultivo, sendo que dois desses (pentamidina e MMV688410) também induziram potencialmente a ocorrência de morte por necrose celular. Outros vinte e quadro compostos apresentaram ação intermediária contra T. evansi, dentre os quais, cinco são fármacos já disponíveis no mercado para tratamento de outras afecções. Utilizando dados de citoxicidade celular disponíveis na literatura e no material de apoio do Pathogen Box®, foi possível indicar o composto MMV688410 como o mais promissor para posteriores estudos de novas drogas tripanocidas. O composto MMV688410 provavelmente inibe a triapanotiona redutase, fato que explica sua baixa citotoxidade, uma vez que esse alvo é exclusivo de tripanossomatídeos, além disso induziu tanto a redução do número de parasitas em cultivo como a morte dos parasitas por necrose celular. Os resultados obtidos neste trabalho fornecem dados promissores para o estudo de novas drogas tripanocidas. Mais pesquisas são necessárias para melhor determinar a ação dos compostos encontrados contra T. evansi.

CANEVER, M. F. Screening and Identification of Compounds Present in Pathogen Box® with anti-Trypanosoma evansi Activity. 2018. Dissertação (Mestrado em Ciência Animal) - Universidade do Estado de Santa Catarina, Lages, 2018. The parasite Trypanosoma evansi, an etiological agent of surra, has a cosmopolitan distribution and although it is initially described as causing the disease in horses, there are reports of infection in innumerable domestic and wild species (dogs, camels, cattle, caprines, capybara, bats, among others). Currently the treatment and prophylaxis of the disease caused by T. evansi are based on the administration of drugs such as suramin, diminazene aceturate, melarsomine and isometamidium. The main limitations in the use of these drugs are associated with toxicity in some species, and reports of treatment resistant strains. In order to find new alternatives for treatment of neglected diseases, Medicines for Malaria Venture developed the Pathogen Box® - a set of plates containing four hundred compounds distributed individually in wells. The objective of this work was to evaluate the anti-T. evansi activity of compounds present in the Pathogen Box® and to identify molecules that could be used in the future in the development of new drugs for treatment and prophylaxis of surra. Among the four hundred compounds analyzed, seven (pentamidine, MMV688410, MMV687273, MMV022478, MMV688763, MMV676602 and auranofin) showed potential activity against T. evansi, reducing the number of cells in culture, two of which (pentamidine and MMV688410) also potentially induced occurrence of death by cellular necrosis. Twenty other compounds showed intermediate action against T. evansi, of which five are drugs already available in the market for treatment of other conditions. Using cell cytotoxicity data available in the literature and in Pathogen Box® support material, it was possible to indicate compound MMV688410 as the most promising for further studies of novel trypanocidal drugs. The compound MMV688410 probably inhibits triapanoethione reductase, which explains its low cytotoxicity, since this target is unique to trypanosomatids, in addition it induced both the reduction of the number of parasites in culture and the death of the parasites by cellular necrosis. The results obtained in this work provide promising data for the development of new trypanocidal drugs, but more studies are needed to better determine the action of the compounds found against T. evansi.

Susceptibility of Trypanosoma evansi in the copaiba oil: in vitro test and in mice experimentally infected with the parasite

Background: Trypanosoma evansi is a flagellate which belongs to the salivate section, commonly observed parasitizing blood of equines, ruminants, pigs, dogs and wild animals in different regions of the world. It causes many losses to farmers due to death of animals and drug spending in endemic areas. The treatment of this disease in Brazil is only performed with diminazene aceturate; however it has been ineffective for many animals. During the last years many studies have been carried out with natural products such as the essential oils. Copaiba oil stands out due some properties described as anti-inflammatory, healing, antiedematogenic, antitumor, parasitic and antibacterial. Therefore, this study aimed to test, in vitro and in vivo, the susceptibility of T. evansi to copaiba oil. Materials, Methods & Results: The oils used in this study were obtained from Copaifera reticulata and Copaifera duckei trees, commonly found in the Tapajos National Forest. The procedure received authorization of IBAMA due the scientific purposes. This study identified three oils identified as copaiba 4-C (C. reticulata), copaiba 5-C (C. duckei) and copaiba 8-C (C. reticulata). The bioassay was performed in vitro using specific culture medium for T. evansi, previously described by Baltz, 1985. Copaiba oil was dissolved in dimethyl sulfoxide (DMSO) and tested in three concentrations (0.5, 1.0 and 2.0%) in culture medium containing the parasite. To the control test (without oil) the same volume of DMSO (10 µL) was added. Dimnazene aceturate was also used as a positive control at 0.5% of concentration. The counting of trypanosomes was performed in triplicate in a Neubauer chamber after 1, 3, and 6 hours after the experiment onset. For the tests in vivo, mice were infected (n = 40) and divided in 5 groups of 8 animals each. Group A consisted of healthy animals and Group B comprised animals infected with T. evansi and untreated. The other groups were infected and treated orally with oil of copaíba 4-C (Group C), copaiba 5-C (Group D) and copaiba 8-C (Group E), using a dose of 0.63 mL/kg/day for five consecutive days at intervals of 24 hours. In vitro tests with copaiba oil showed a reduction in the number of alive trypanosomes for the three tested concentrations, when compared to the control test after 1 and 3 h, similar to what occurred with testing aceturate. At 6 hours, it was not observed alive parasites in the test groups, differently from the control group which had an increase of trypanosomes compared to the time zero. The trypanocidal activity had a dose-dependent effect. In the in vivo experiment, the oil of copaiba administered orally had no curative efficacy for any of the groups; however group D treated with C. duckei showed prolonged longevity of the mice when compared to the groups B and C. Discussion: Trypanosoma cruzi and Leishmania amazonensis have been challenged on their susceptibility to oil of copaiba, with obtention of trypanocidal and leishmanicidal effects, similar process thet occurred in this study with T. evansi. According to scientific literature the copaíba oil increases the membrane permeability, as well as provides the depolarization of the mitochondrial membrane in parasite cells. A group of mice in this study showed prolonged longevity, showing that the variation of their compositions influence the trypanocidal effect. Based on these results it was concluded that the T. evansi may is susceptible to the oil of copaiba. Therefore, it can be natural product used as a new alternative and supplementar activity in the treatment of this protozoan, as have been suggested for leishmaniasis.

PADRONIZAÇÃO DE UM ANTÍGENO TAMPONADO PARA PESQUISA DE ANTICORPOS ANTI -Trypanosoma evansi EM EQUINOS

Surra, também conhecida como Mal das Cadeiras na América Latina, é uma doença infecciosa causada pelo Trypanosoma evansi (T. evansi). Descrita primariamente nas regiões tropicais e subtropicais da África, Ásia, América Central, acomete grande número de espécies de animais domésticos e selvagens (equinos, camelídeos bovinos, búfalos, ovinos, caprinos, suínos, felinos, cães, capivaras e morcegos hematófagos), causando morte de animais, diminuição da produção e elevados e gastos com tratamentos. No Brasil não existem dados oficiais acerca da circulação do agente, apenas estudos regionalizados. Santa Catarina é considerada zona livre da doença. O controle da infecção está baseado no diagnóstico rápido seguido do tratamento dos animais doentes. O exame microscópico direto, é o teste mais utilizado para o diagnóstico da infecção no Brasil, entretanto, apresenta baixa especificidade e sensibilidade, levando possivelmente ao sub - diagnóstico da infecção, principalmente na fase crônica. Assim, o objetivo deste trabalho é avaliar um ensaio de soroaglutinação rápida (SAR/Te) para sorodiagnóstico de triagem da infecção por T. evansi em equinos. Além disso, este estudo descreve as características clínicas, parasitológicas e hematobioquímicas no primeiro caso autóctone de surra em equinos no Estado de Santa Catarina, Brasil. Deste modo, esta proposta visa contribuir com as estratégias de vigilância e controle da surra no país.

Trypanosoma evansi is the causative agent of surra or Mal das Caderas (in Brazil). The disease is present in Africa, Asia and Latin America. It can affect a very large range of domestic and wild hosts ( equines, camelids, cattle, buffaloes, sheep, goats, pigs, dogs, capybaras and vampire bats) causing high mortality, decrease of production and expenses with treatments. In Brazil, there are no epizootiological data on the circulation of the agent, only regionalized studies. Santa Catarina State is considered a free zone of trypanosomiasis. The disease control, is based on rapid diagnosis of infection followed by treatment of animals. Direct microscopic examination is the primary test for the diagnosis of infection in Brazil, however, it presents low specificity and sensitivity, possibly leading to underdiagnosis of infection, mainly in the chronic stage. Thus, the main aim of this study is to evaluate a rapid test of serum agglutination for diagnosis of T. evansi infection in horses. In addition, this work describes the clinical, parasitological and haemato biochemical parameters in the first autochthonous outbreak of Surra in horses in the State of Santa Catarina, Brazil.

Tripanossomose Bovina em Minas Gerais, 2011: Soroprevalência e fatores de risco

A tripanossomose bovina é responsável por grandes perdas econômicas na África e na América Latina. Nas Américas, Trypanosoma vivax é o agente causador da doença em bovinos, sendo transmitido mecanicamente por insetos hematófagos e fômites. Sua origem no continente americano ocorreu através da importação de animais do Oeste da África e no Brasil os primeiros relatos foram na região Norte com posterior disseminação para o Pantanal e na última década surtos foram relatados em diversas regiões do país, inclusive em Minas Gerais. Diante disso, objetivou-se determinar a prevalência sorológica da tripanossomose bovina e avaliar os fatores de risco associados à doença no estado de Minas Gerais. Em 2011, realizou-se um estudo transversal em Minas Gerais, no qual o estado foi estratificado em sete regiões de acordo com as características agroprodutivas: 1. Noroeste, Norte e Nordeste; 2. Leste; 3. Central; 4. Zona da Mata; 5. Sul e Sudoeste; 6. Alto Paranaíba; 7. Triângulo Mineiro. Ao todo, amostrou-se aleatoriamente 2185 propriedades, das quais amostras de soro de um animal provenientes de cada rebanho foram submetidas à reação de imunofluorescência indireta para a detecção de anticorpos anti-T. vivax. A soroprevalência das propriedades para tripanossomose bovina no estado de Minas Gerais foi 2,38% (95% IC: 1,68-3,08%). Entre os estratos a prevalência variou de 0,69% na região Leste (estrato 2) a 3,7% nas regiões Sul e Sudoeste (estrato 5), porém não houve diferença significativa. A análise de fator de risco indicou que rebanhos nos quais os proprietários alegaram realizar o teste de brucelose e comprar animais de comerciantes de gado tiveram maior chance de ocorrência da doença, com razão de chance de 2,75 (95% IC: 1,37- 5,51) e 3,36 (95% IC: 1,31-8,59), respectivamente. Não houve a presença de aglomerados entre as propriedades que apresentaram animais soro reagentes. O presente estudo é o primeiro a revelar a prevalência da tripanossomose bovina no estado de Minas Gerais. Os resultados permitiram observar que a prevalência foi baixa, no entanto a doença já se encontrava distribuída homogeneamente em todo o estado. Adicionalmente, realizar o teste de brucelose exerce influência indireta sobre a ocorrência da doença, enquanto comprar animais de comerciantes de gado tem impacto direto sobre a ocorrência da tripanossomose bovina em Minas Gerais, exigindo educação sanitária para os proprietários e utilização de medidas de biosseguridade nas propriedades.

Bovine trypanosomosis is responsible for great economic losses in Africa and Latin America. In the Americas, Trypanosoma vivax is the mainly cause for the disease in cattle, being mechanically transmitted by blood-sucking insects and fomites. The agents of the disease were brought to South America for the first time, from Africa, through imported animals, caracterizing its origin in the Americas. The first report was emited in the north of Brazil, with subsequent spread to the Pantanal and, in the last decade, outbreaks were reported in several regions of the country, including Minas Gerais. The research objective was to determine the serological prevalence of bovine trypanosomosis and identify risk factors associated with the disease in Minas Gerais state. In 2011, a cross sectional study was performed in Minas Gerais, in which the state was divided into seven regions according to agricultural production characteristics: 1. Northwest, North and Northeast; 2. Eastern; 3. Central; 4. Forest Zone; 5. South and Southwest; 6. Alto Paranaíba; 7. Triângulo Mineiro. Among all regions, 2185 properties were sampled randomly, of which serum samples were collected and subjected to indirect immunofluorescence assay for the detection of anti-T. vivax. The prevalence for bovine trypanosomosis on properties in Minas Gerais state was 2.38% (95% CI: 1.68 to 3.08%). Among strata the prevalence ranged from 0.69% in the eastern region (stratum 2) to 3.7% in the South and Southwest (stratum 5), but there was no significant difference. Risk factor analysis indicated that herds in which the owners claimed to perform brucellosis test and to buy animals from cattle traders, had greater chance of occurrence of the disease, with an odds ratio of 2.75 (95% CI: 1.37 to 5.51) and 3.36 (95% CI: 1.31 to 8.59), respectively. There was no presence of agglomerated between farms with animal serum reagents. This study is the first to reveal the prevalence of bovine trypanosomosis in Minas Gerais state. Results showed that the prevalence was low, however the disease was already homogeneously distributed throughout the state. Additionally, perform brucellosis test exerts indirect influence on the occurrence of the disease, while buying animals from livestock dealers have a direct impact on the occurrence of bovine trypanosomosis in Minas Gerais, requiring health education for owners and use of biosecurity measures in the properties.

A new therherapeutic prrotocol f for dogs infectted with Trrypanosoma evansi

Background: Trypanosomosis is a disease caused by a flagellate protozoan known as Trypanosoma evansi, transmitted by hematophagous insects. It parasites showed a large diversity of mammalian hosts. Dogs may show clinical changes such as weight loss, progressive weakness, anorexia, anemia, intermittent fever, conjunctivitis, swelling of limbs and increased of superficial lymph nodes. Treatment of trypanosomosis relies on the use of diminazene aceturate which is effective for the treatment of disease in infected animals. However, a single dose of drug are not effective for horses, mules and dogs, since drug neither cross the blood-brain barrier or has insufficient doses to control the T. evansi infection. Therefore, the present study aimed to report the curative efficacy of a new therapeutic protocol, based on diminazene aceturate, for dogs infected with T. evansi. Case: The treatment against trypanosomosis was performed in a dog, male, two years old, from the municipality of Uruguaiana, RS, Brazil.. The animal showing clinical signs such as apathy, vomit, increase of left submandibular lymph node, edema of the left face and change of gait in the hind limbs when it was evaluated by veterinarians. The hematological and biochemical parameters revealed normocytic-hypochromic anemia, thrombocytopenia, hyperglobulinemia and hypoalbuminemia. Trypomastigotes of T. evansi were identified in blood smears stained by panoptic method. The parasitism by T. evansi was confirmed by blood inoculation in two rats (xenodiagnosis) and by PCR T. evansi-specific. The canine was treated with diminazene aceturate (intramuscular injection) using a dose of 3.5 mg kg-1 for 5 days at 24h of intervals. After treatment the dog showed clinical signs of health improvement, and clinical signs disappeared after the seventh day of treatment. The parasite was not found in blood smears after the third day of treatment and PCR was negative on days 30 and 50 post-treatment. During the treatment signs of drug intoxication were not observed, as well as hepatic and renal functions were not affected. The animal showed normal biochemical and hematological parameters after 30 days of treatment. Discussion: In this study, the treatment tested was effective, leading to the cure of the disease. Previously, the same protocol was used for cats experimentally infected with T. evansi, obtaining 85.7% (6/7) of curative efficacy. In a comparative study of doses of diminazene aceturate in rats infected with T. evansi, inefficiency and death of rats treated with a single dose of 3.5 and 7.0 mg kg-1 were observed. In contrast, the cure in rats occurred when animals received a dose of 3.5 and 7.0 mg kg-1 during five consecutive days. The return of the parasitemia after treatment may be related to the impossibility of the medicament pass through the blood-brain barrier or the doses is insufficient. Our data reveal that five-dose protocol obtained higher efficiency because it provided greater passage of drug molecules through blood-brain barrier, which could eliminate the parasite from brain. After treatment, all clinical signs disappeared, biochemical and hematological parameters returned to normal levels, allowing us to conclude that this new protocol tested was effective to cure of this disease in dogs.

A new therherapeutic prrotocol f for dogs infectted with Trrypanosoma evansi

Background: Trypanosomosis is a disease caused by a flagellate protozoan known as Trypanosoma evansi, transmitted by hematophagous insects. It parasites showed a large diversity of mammalian hosts. Dogs may show clinical changes such as weight loss, progressive weakness, anorexia, anemia, intermittent fever, conjunctivitis, swelling of limbs and increased of superficial lymph nodes. Treatment of trypanosomosis relies on the use of diminazene aceturate which is effective for the treatment of disease in infected animals. However, a single dose of drug are not effective for horses, mules and dogs, since drug neither cross the blood-brain barrier or has insufficient doses to control the T. evansi infection. Therefore, the present study aimed to report the curative efficacy of a new therapeutic protocol, based on diminazene aceturate, for dogs infected with T. evansi. Case: The treatment against trypanosomosis was performed in a dog, male, two years old, from the municipality of Uruguaiana, RS, Brazil.. The animal showing clinical signs such as apathy, vomit, increase of left submandibular lymph node, edema of the left face and change of gait in the hind limbs when it was evaluated by veterinarians. The hematological and biochemical parameters revealed normocytic-hypochromic anemia, thrombocytopenia, hyperglobulinemia and hypoalbuminemia. Trypomastigotes of T. evansi were identified in blood smears stained by panoptic method. The parasitism by T. evansi was confirmed by blood inoculation in two rats (xenodiagnosis) and by PCR T. evansi-specific. The canine was treated with diminazene aceturate (intramuscular injection) using a dose of 3.5 mg kg-1 for 5 days at 24h of intervals. After treatment the dog showed clinical signs of health improvement, and clinical signs disappeared after the seventh day of treatment. The parasite was not found in blood smears after the third day of treatment and PCR was negative on days 30 and 50 post-treatment. During the treatment signs of drug intoxication were not observed, as well as hepatic and renal functions were not affected. The animal showed normal biochemical and hematological parameters after 30 days of treatment. Discussion: In this study, the treatment tested was effective, leading to the cure of the disease. Previously, the same protocol was used for cats experimentally infected with T. evansi, obtaining 85.7% (6/7) of curative efficacy. In a comparative study of doses of diminazene aceturate in rats infected with T. evansi, inefficiency and death of rats treated with a single dose of 3.5 and 7.0 mg kg-1 were observed. In contrast, the cure in rats occurred when animals received a dose of 3.5 and 7.0 mg kg-1 during five consecutive days. The return of the parasitemia after treatment may be related to the impossibility of the medicament pass through the blood-brain barrier or the doses is insufficient. Our data reveal that five-dose protocol obtained higher efficiency because it provided greater passage of drug molecules through blood-brain barrier, which could eliminate the parasite from brain. After treatment, all clinical signs disappeared, biochemical and hematological parameters returned to normal levels, allowing us to conclude that this new protocol tested was effective to cure of this disease in dogs.(AU)

Experimental Infection by Tripanossoma evansi in Rabbits: Levels of Sodium, Potassium, Calcium and Phosphorus in Serum

Background: Trypanosoma evansi is the most widely distributed of the pathogenic African animal trypanosomes, affecting domestic livestock and wildlife in country. The animals presented clinical sings as anemia, emaciation, apathy, recurrent fever , enlarged lymph nodes, edema and abortion The minerals have different functions in the organism, and an imbalance, either by excess or deficiency, or a pathological condition, causes alterations in the respective serum levels, as well as in trypanosomosis. Therefore, the aim of this study was to evaluate the concentrations of sodium, potassium, calcium and phosphorus in blood serum of rabbits experimentally infected with Trypanosoma evansi. Materials, Methods & Results: Twelve adult female Oryctolagus cuniculus, weighing average 3.9 kg, were used. Rabbits were divided into two groups, a control group with six animals (rabbits 1-6) and an infected group with six animals (rabbits 7-12). Animals from trypanosome-infected groups were inoculated intraperitoneally with 0.5 mL of rat blood containing 10 8 trypanosomes (Day 1). Control group received physiological solution by the same route. Parasitemia was estimated daily for 118 days post- inoculation (PI) by microscopic examination of smears. Blood samples for hematology and evaluation of serum minerals were collected at days 1, 5, 20, 35, 50, 80 and 118 PI. Hematocrit was evaluated for monitoring of the disease. Inductively coupled plasma optical emission spectrometry (ICP OES) was used to measure the levels of sodium, potassium, calcium and phosphorus. Hyporexia, edema and fever were clinical signs associated with change in the levels of the minerals. A decrease in the number of red blood cells was only observed at day 5 post-inoculation. Significant differences were observed among groups (P < 0.05) in minerals levels. Sodium and calcium were reduced at days 35, 50, 80 and 118 PI. [...]