Beriberi is caused by thiamine deficiency. Early 20th century epidemics in Japan were attributed to rice contaminated by citreoviridin mycotoxin. Our investigation of an outbreak of beriberi in Brazil showed an association of beriberi with the consumption of poor quality subsistence farming rice, although, unlike other investigators of this outbreak, we did not identify citreoviridin producing fungi in the implicated rice.

O estudo objetivou descrever dois surtos de intoxicação por exposição à rapadura, ocorridos em três municípios do estado do Rio Grande do Norte, entre janeiro e fevereiro de 2008. Foi conduzida uma investigação epidemiológica com a realização de estudo de caso. Outras investigações, laboratorial e ambiental, complementaram o quadro de informações sobre os surtos. Foram oito casos prováveis por exposição à rapadura, dos quais cinco por consumo do produto (um evoluiu para óbito) e três por proximidade física. As manifestações clínicas foram compatíveis com intoxicação por organofosforados. Outros sintomas apresentados podem estar relacionados com a presença de SO2, como rouquidão, lacrimejamento, dor nos olhos e ulceração corneana. A acetilcolinesterase eritrocitária resultou alterada para um dos pacientes que consumiu rapadura. Ocorreram dois surtos de intoxicação exógena: um por circunstância acidental e o outro, em decorrência do primeiro, por intoxicação ocupacional, cujo alimento implicado foi a rapadura contaminada com metamidofós e sulfito (SO2). A quantidade de metamidofós presente na rapadura consumida por dois casos foi 3.000 vezes maior que a ingestão diária aceitável para essa substância em humanos. Recomendam-se a adoção de medidas de saúde pública com a finalidade de minimizar a incidência de casos de intoxicação exógena e problemas decorrentes e prevenir surtos ocasionados por substâncias químicas, como as investigadas neste estudo.

In this study, we assessed the larvivorous activity of Oxydoras kneri against Culicinae larvae in laboratory experiments to evaluate their suitability as a biological control. First, analysis of stomach content was performed to verify the feeding habits of the fish in their natural habitat. The behavior was then verified in aquarium experiments by feeding 2700 larvae to each fish. The feeding preference of the fish was evaluated in further experiments in which larvae and commercial fish food were offered, either separately or simultaneously. For both methods, the evaluation was performed by counting the number of adult mosquitoes that emerged during a 60-h observation period. The laboratory was maintained at relatively stable temperature and humidity. The stomach content of 9 specimens of O. kneri captured in the Cuiabá River contained 26.5% insect larvae, with 11.5% exclusively from Diptera insects. The emergence of adults from insect larvae was not influenced by the presence of O. kneri. However, emergence was statistically lower in aquaria when the larvae were placed as food for the fish. The consumption of larvae and granulated commercial fish food was similar during a 60-h observation period, even when these items were offered separately or simultaneously. Since O. kneri are ubiquitous in the Amazon region, this finding highlights their potential role in the biological control of Culicidae mosquito larvae growing in fish farm tanks. However, further studies are required to evaluate their behavior in the field and the operational difficulties of their use as a biological control.