Effect of environmental factors in reducing the prevalence of schistosomiasis in schoolchildren: An analysis of three extensive national prevalence surveys in Brazil (1950-2018).

Background: Over seven decades, Brazil has made admirable progress in controlling schistosomiasis, and a frequent question about the explanation for this reduction refers to the effect of improving environmental factors in the country. This article seeks to identify factors related to the change in the epidemiological situation of schistosomiasis mansoni infection by analyzing three national prevalence surveys conducted since 1950.

Methodology/principal Findings: This is an ecological study analyzing an unbalanced panel of data based on national surveys and considering the municipality as the unit of analysis.

Sewerage as a protective factor for prevalence of hookworm infection in schoolchildren in Brazil: A multilevel ecological analysis of national prevalence surveys (1950-2018).

Introduction: The prevalence of hookworm infection in Brazil has decreased considerably in recent decades. However, there is no definitive consensus as to which changes have contributed to this reduction. A hypothesis is that improvements in environmental factors have contributed to lowering the parasite load and the level of host-parasite contact.

Water, sanitation and schistosomiasis mansoni: a study based on the Brazilian National Prevalence Survey (2011-2015).

This study aimed to explore the association between water, sanitation, and the prevalence of schistosomiasis mansoni in students aged 7 to 17 years from all 27 federative units in Brazil. It was a cross-sectional study conducted based on data on the prevalence of schistosomiasis mansoni referring to 197,567 students from 521 Brazilian municipalities, who participated in the National Survey on the Prevalence of Schistosomiasis Mansoni and Soil-transmitted Helminth Infections (2011-2015). Univariable and multivariable generalized linear models of the negative binomial type were adjusted using 25 and 5% significance levels, respectively, considering municipalities as the unit of analysis.

Intervention for promoting intake of fruits and vegetables in Brazilians: a randomised controlled trial.

Objective: To evaluate the effectiveness of a nutritional intervention to promote fruit and vegetable (FV) intake.

Design: A randomised controlled community trial was conducted to evaluate the effectiveness of a 7-month nutritional intervention and to promote FV intake, separately and together. All participants attended physical exercise sessions.

Association between water and sanitation and soil-transmitted helminthiases: Analysis of the Brazilian National Survey of Prevalence (2011-2015).

Background: Most of the studies conducted in Brazil assessing the relationship between water, sanitation and hygiene (WASH) and Soil-transmitted helminth (STH) infections, have focused on cases, reflecting the reality of small areas and not of a countrywide situation. In order to fill this gap, the current paper presents an epidemiological study exploring the association between water and sanitation and STHs prevalence in students from 7 to 17 years old, in all 27 Brazilian Federation Units.

Methods: Three ecological studies were carried out considering the prevalence of ascariasis, trichuriasis, and hookworm as outcome variables.