Seasonality of Human Leptospirosis in Reunion Island (Indian Ocean) and Its Association with Meteorological Data

Background: Leptospirosis is a disease which occurs worldwide but particularly affects tropical areas. Transmission of the disease is dependent on its excretion by reservoir animals and the presence of moist environment which allows the survival of the bacteria. Methods and Findings: A retrospective study was undertaken to describe seasonal patterns of human leptospirosis cases reported by the Centre National de Re´fe´rences des Leptospiroses (CNRL, Pasteur Institute, Paris) between 1998 and 2008, to determine if there was an association between the occurrence of diagnosed cases and rainfall, temperature and global solar radiation (GSR). Meteorological data were recorded in the town of Saint-Beno?¿t (Me´te´o France ''Beaufonds-Miria'' station), located on the windward (East) coast. Time-series analysis was used to identify the variables that best described and predicted the occurrence of cases of leptospirosis on the island. Six hundred and thirteen cases were reported during the 11-year study period, and 359 cases (58.56%) were diagnosed between February and May. A significant correlation was identified between the number of cases in a given month and the associated cumulated rainfall as well as the mean monthly temperature recorded 2 months prior to diagnosis (r = 0.28 and r = 0.23 respectively). The predictive model includes the number of cases of leptospirosis recorded 1 month prior to diagnosis (b = 0.193), the cumulated monthly rainfall recorded 2 months prior to diagnosis (b = 0.145), the average monthly temperature recorded 0 month prior to diagnosis (b = 3.836), and the average monthly GSR recorded 0 month prior to diagnosis (b =21.293). Conclusions: Leptospirosis has a seasonal distribution in Reunion Island. Meteorological data can be used to predict the occurrence of the disease and our statistical model can help to implement seasonal prevention measures. (Résumé d'auteur

Isolation and Characterization of New Leptospira Genotypes from Patients in Mayotte (Indian Ocean)

Leptospirosis has been recognized as an increasing public health problem affecting poor people from developing countries and tropical regions. However, the epidemiology of leptospirosis remains poorly understood in remote parts of the world. In this study of patients from the island of Mayotte, we isolated 22 strains from the blood of patients during the acute phase of illness. The pathogenic Leptospira strains were characterized by serology and various molecular typing methods. Based on serological data, serogroup Mini appears to be the dominant cause of leptospirosis in Mayotte. Further molecular characterization of these isolates allowed the identification of 10 pathogenic Leptospira genotypes that could correspond to previously unknown serovars. Further progress in our understanding of the epidemiology of Leptospira circulating genotypes in highly endemic regions should contribute to the development of novel strategies for the diagnosis and prevention of this neglected emerging disease

Topologia do risco de acidentes do trabalho em Piracicaba, SP Spatial distribution of risks for work-related injuries in a city of Southeastern e Brazil

OBJETIVO: Analisar a distribuição espacial do risco de acidente do trabalho controlado por variáveis nutricionais e outras co-variáveis. MÉTODOS: Estudo caso-controle espacial de base hospitalar, tendo como variável de interesse a localização espacial dos acidentes do trabalho. Foram amostrados 794 trabalhadores, no período de maio a outubro de 2004. Os critérios de inclusão para casos (N=263) foram: ser trabalhador acidentado do trabalho, morador de Piracicaba, com idade entre 15 e 60 anos, e atendido em centro de ortopedia e traumatologia. Os controles (N=531) tiveram o mesmo critério de idade e residência na cidade, exceto que o acidente não era do trabalho, tendo sido considerandos também trabalhadores acompanhantes dos casos. A distribuição espacial da estimativa baseou-se no ajuste do modelo aditivo generalizado, tendo as coordenadas geográficas dos casos e controles como componente espacial não linear e as demais co-variáveis como componente linear. RESULTADOS: A variação da estimativa do risco espacial de acidentes do trabalho, controlada por sexo (OR=1,87; p<0,001), escolaridade (OR=0,85; p<0,0001), ser autônomo (OR=0,36; p<0,01) e circunferência de cintura (OR=0,98; p=0,05), mostra que as regiões de maior risco foram a centro-leste e a área que forma um "corredor" entre as regiões sul-norte. CONCLUSÕES: O uso de ferramentas de geoprocessamento e a consideração de variáveis nutricionais fornecem elementos para a compreensão das relações que compõem o risco de acidentes do trabalho, sendo oportuna a continuidade de investigações que contemplem esses fatores.<br>OBJECTIVE: To assess spatial distribution of risks for work-related injuries controlled for nutritional variables and other covariables. METHODS: Hospital-based spatial case-control study with work-related injuries spatial distribution as the main variable of interest. A total of 794 workers were selected between May and October 2004. Inclusion criteria for cases (N=263) were: worker with work-related injury; living in Piracicaba (Southeastern Brazil); age between 15 and 60 years old; and cared at an orthopedics and trauma center. Controls (N=531) met the same criteria for age and residence, but had non-work-related injuries and workers accompanying cases were included as well. Spatial distribution was estimated by adjusting a generalized additive model with geographical coordinates of cases and controls as spatial non-linear component and the remaining covariables as linear components. RESULTS: The variation of estimated spatial risks for work-related injuries controlled for gender (OR=1.87, p<0.001), schooling (OR=0.85, p<0.0001), self-employed (OR=0.36, p<0.01), and waist circumference (OR=0.98, p=0.05) showed that the mideastern area and north-to-south "strip" have higher risk for injuries. CONCLUSIONS: The use of geoprocessing tools and nutritional variables can provide input for understanding the universe of risks for work-related injuries. Further investigation exploring these factors is needed