Introduction Leptospirosis has emerged as an important health problem in developing countries due to the growth of slum settlements worldwide, where poor sanitation favours rat-borne transmission. Large urban epidemics occur during seasonal periods of heavy rainfall. However, a detailed analysis has not been performed to determine how rainfall, as well as other climatic factors, specifically influences the risk of leptospirosis in these endemic settings. Methods We analysed data from 2083

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... pirosis cases which were identified during active population-based surveillance performed in the city of Salvador, Brazil between 1996 and 2010. Information on daily rainfall, humidity and temperature were obtained for the same period. A generalised additive model was fitted, using a negative binomial distribution for weekly aggregated data (729 weeks). We incorporated a non-parametric term to estimate the time trend and a sin-cosine term to control for seasonal confounding. Results Rainfall and humidity were positively associated with the number of cases two weeks later, linearly and without a threshold. Temperature protected, even though the range between maximum and minimum temperatures is small: from 22 to 338C. A decreasing trend was highly significant, possibly due to intervention of sewerage and garbage collection systems. Conclusion Leptospirosis is expected to become an increasingly important slum health problem as predicted global climate change and growth of the world's slum population evolves, and models adequate to estimate the impact of both environment and climate variables on incidence of all environmental related diseases should be incorporated in the epidemiologists toolbox. Introduction The high magnitude and wide geographic distribution of parasitic infections, coupled with the negative impact that may cause the human body given to these infections have an important position among the major health problems of the population especially in developing countries. The objective of this study is to describe the occurrence of geohelminth in children of the northnortheast Brazil and to identify environmental and socioeconomic risk factors. Methods Coprologic surveys were carried out to estimate the prevalence of geohelminth infections among in children in 10 Brazilians municipalities with low Human Development Indexes. Socioeconomic and environmental data were obtained from the children's parents or guardians, and fecal samples were examined. The proportion of geohelminth infections according variables of interest was calculated. Risk factors were evaluated using multilevel logistic regression. Of the 2523 children studied, 36.5% were affected by one or more geohelminths (Ascaris lumbricoides: 25.1%; hookworm: 15.3%; Trichuris trichiura: 12.2%). The overall frequency of geohelminth infections was 45.7% in rural areas and 32.2% in urban areas. Low family income (OR¼1.75; 1.38e2.23), low maternal education level (OR¼1.69; 1.39e2.06), presence of garbage near the home (OR¼1.50; 1.22e1.84) and an increased number of individuals in the household (OR¼1.41; 1.17e1.71) were associated with infection. Conclusion The geohelminth infections were strongly related with socioeconomic conditions, stressing the importance of public interventions targeted to improve life conditions as part of its sustainable prevention.