Claviceps purpurea e Bipolaris sp. como causa de ergotismo em bovinos no estado de Santa Catarina / Claviceps purpurea e Bipolaris sp. as a cause of ergotism in cattle in Santa Catarina State

Claviceps purpurea é o fungo associado ao ergotismo. Esta é uma enfermidade causada pela ingestão de escleródios chamados de ergot, que contém alcalóides que atuam em receptores adrenérgicos, dopaminérgicos e seratoninérgicos causando efeito direto em vasos sanguíneos, musculatura lisa e sistema nervoso central e autônomo. Descrevem-se dados epidemiológicos, sinais clínicos e lesões de uma enfermidade de bovinos caracterizada por hipertermia, taquicardia, taquipneia e ulcerações na coroa do casco de bovinos. Entre 2000 e 2014 foram diagnosticados 13 surtos, três da forma distérmica, sete da forma gangrenosa e três da forma convulsiva. Porém, em cinco destes sete surtos, nos locais onde esses animais pastoreavam havia alta incidência de inflorescências de Sporobolus indicus conhecido como "capim-mourão", infectadas por um fungo com coloração enegrecida, identificado como Bipolaris sp. A enfermidade foi reproduzida experimentalmente em cinco bovinos com a administração destas inflorescências. Os bovinos em experimentação receberam inflorescências de S. indicus respectivamente nas doses diárias de 0,1g/kg, 0,2g/kg, 0,2g/kg, 0,26g/kg e 0,34g/kg por um período de 4, 7, 9 e 30 dias. Após três a sete dias de ingestão das inflorescências infectadas, quatro dos cinco bovinos apresentaram diarreia e manifestaram taquicardia, taquipneia e hipertermia em algum período durante a ingestão. Estes sinais coincidiram com os dias mais quentes deste período. Um bovino manifestou hiperemia na coroa do casco e perda de pêlos da extremidade da cauda. Baseado na reprodução experimental é possível afirmar que o capim Sporobolus indicus infectado pelo fungo Bipolaris sp é capaz de causar diarreia, hipertermia, taquicardia, taquipneia, hiperemia na coroa do casco e perda de pêlos da extremidade da cauda.(AU)

Claviceps purpurea is the fungus associated with ergotism. Ergotism is a disease caused by the ingestion of esclerodios called ergot, which contains alkaloids that act on dopaminergic and adrenergic receptors, causing seratoninergic effect on blood vessels, smooth muscles and central nervous and autonomic system. The present study describes epidemiological data, clinical signs and lesions of a bovine cattle disease characterized by hyperthermia, tachycardia, tachypnea and injuries in the coronary band of the hooves. Initially the cause was attributed to the fungus Claviceps purpurea. Between 2000 and 2014, 13 outbreaks were described, being three of distermic form, seven of gangrenous and three of the convulsive form. However, in five out of the seven of the gangrenous form outbreaks, it has been observed a high incidence of smut grass (Sporobolus indicus) inflorescences infected by a blackened fungus, classified as Bipolaris sp., in the places where the bovine grazed. The disease was reproduced experimentally by administration of inflorescences of smut grass contaminated by Bipolaris sp. Five bovine received daily doses of 0.1g/kg, 0.2g/kg, 0.2g/kg, 0.26g/kg and 0.34g/kg during 4, 7, 9, 30 and 30 days respectively. After three to seven days of eating contaminated inflorescences four cattle had diarrhea, tachycardia, tachypnea and intermittent hyperthermia. These clinical signs happened on the warmest days and during the warmest temperatures of the day. A bovine showed hyperemia in the coronary band of the hoof and loss of tail tip hair. According to data obtained during the experimental reproduction, smut grass contaminated by Bipolaris sp. can cause hyperthermia, tachycardia, tachypnea, injuries in the coronary band of the hoof and loss of the tail tip hair in bovine cattle.(AU)

Intoxicação espontânea e experimental por tifton 68 (Cynodon nlemfuensis Vanderyst) em bovinos / Spontaneous and experimental poisoning by tifton 68 (Cynodon nlemfuensis Vanderyst) in cattle

Tifton 68 (Cynodon nlemfuensis Vanderyst) é uma gramínea cultivada na região sul do Brasil, responsável por manifestações clínicas superagudas de dispneia, dificuldade de deglutição, tremores musculares, timpanismo e decúbito em bovinos. A morte ocorre rapidamente após o início dos primeiros sinais e não são encontradas alterações macro e microscópicas significativas. O presente estudo descreve os aspectos epidemiológicos, clínicos e lesionais da intoxicação espontânea por tifton 68 que ocorreu nos municípios de Rio do Sul, Pouso Redondo, Taió e Rio do Campo, estado de Santa Catarina, Brasil, nos anos de 1996, 1997, 1998 e 2010, respectivamente. Experimentalmente foram avaliadas a presença de ácido cianídrico nas folhas verdes e secas desta planta, através do teste do papel picrossódico e a reversão da intoxicação pela utilização de uma solução antídoto específica de tiossulfato de sódio e nitrito de sódio. A reprodução experimental consistiu na administração de folhas verdes de tifton 68 para dois bovinos com doses a partir de 10,3g/kg. O quadro de intoxicação cianogênica foi confirmado pela imediata resposta ao tratamento intravenoso com a solução antídoto. As amostras da planta verde forneceram resposta positiva ao teste do papel picrossódico. O feno de tifton 68 não demonstrou qualquer toxicidade, mesmo em altas doses (18 e 27g/kg), sendo seguro para a alimentação de bovinos.(AU)

Tifton 68 (Cynodon nlemfuensis Vanderyst) is a grass cultivated in southern Brazil which causes peracute clinical manifestations including dyspnea, swallowing difficulties, muscular tremors, tympanism and recumbency in cattle. Animal's death occurs rapidly after the onset of clinical signs and neither macroscopic nor microscopic lesions have been found. This paper describes the epidemiology, clinical findings and lesions of spontaneous poisoning by tifton 68 in cattle in the municipalities of Rio do Sul, Pouso Redondo, Taió and Rio do Campo in the state of Santa Catarina, Brazil, in 1996, 1997, 1998 and 2010 respectively. The presence of hydrocyanic acid was experimentally estimated in green and dried leaves through the picric acid paper test and poisoning treatment using a specific antidote solution of sodium thiosulfate and sodium nitrite. The poisoning was experimentally reproduced by the administration of tifton 68 green leaves to two cattle at a starting dose of 10.3 g/kg. The cyanide poisoning was confirmed by the immediate response to treatment with intravenous antidote. The samples of tifton 68 green leaves gave positive response in the picric acid paper test. The hay of tifton 68 showed no toxicity even at high doses (18 and 27 g/kg) and it is safe for cattle consumption.(AU)

The feasibility of a school-based VI polysaccharide vaccine mass immunization campaign in Hue City, central Vietnam: streamlining a typhoid fever preventive strategy.

We report the coverage, safety, and logistics of a school-based typhoid fever immunization campaign that took place in Hue City, central Vietnam; a typhoid fever endemic area. A cluster-randomized evaluation-blinded controlled trial was designed where 68 schools (cluster) were randomly allocated the single dose Vi polysaccharide vaccine (Typherix) or the active control hepatitis A vaccine (Havrix). A safety surveillance system was implemented. A total of 32,267 children were immunized with a coverage of 57.5%. Strong predictors for vaccination were attending primary schools, peri-urban location of the school, and low family income. Human resources were mainly schoolteachers and the campaign was completed in about 1 month. Most adverse events reported were mild. Safe injection and safe sharp-waste disposal practices were followed. A typhoid fever school-based immunization campaign was safe and logistically possible. Coverage was moderate and can be interpreted as the minimum that could have been achievable because individual written informed consent procedures were sought for the first time in Hue City and the trial nature of the campaign. The lessons learned, together with cost-effectiveness results to be obtained by the end of follow-up period, will hopefully accelerate the introduction of Vi typhoid fever vaccine in Vietnam.

The role of epidemiology in the introduction of vi polysaccharide typhoid fever vaccines in Asia.

Despite the availability of at least two licensed typhoid fever vaccines--injectable sub-unit Vi polysaccharide vaccine and live, oral Ty21a vaccine--for the last decade, these vaccines have not been widely introduced in public-health programmes in countries endemic for typhoid fever. The goal of the multidisciplinary DOMI (Diseases of the Most Impoverished) typhoid fever programme is to generate policy-relevant data to support public decision-making regarding the introduction of Vi polysaccharide typhoid fever immunization programmes in China, Viet Nam, Pakistan, India, Bangladesh, and Indonesia. Through epidemiological studies, the DOMI Programme is generating these data and is offering a model for the accelerated, rational introduction of new vaccines into health programmes in low-income countries. Practical and specific examples of the role of epidemiology are described in this paper. These examples cover: (a) selection of available typhoid fever vaccines to be introduced in the programme, (b) generation of policy-relevant data, (c) providing the 'backbone' for the implementation of other multidisciplinary projects, and (d) generation of unexpected but useful information relevant for the introduction of vaccines. Epidemiological studies contribute to all stages of development of vaccine evaluation and introduction.