Reducing Occurrence of Giardia duodenalis in Children Living in Semiarid Regions: Impact of a Large Scale Rainwater Harvesting Initiative

Abstract

BackgroundIn Brazil, about two million people living in rural semiarid regions were benefited with the construction of rainwater cement cisterns, as an initiative from the program “One Million Cisterns” (P1MC). Nevertheless, few epidemiological studies have been conducted to assess health risks or protection effects associated with consumption of this water source. The aim of this study was to evaluate whether access to rainwater harvesting cisterns is associated with the decrease in the occurrence of Giardia duodenalis infections in children, compared to other children living in households supplied by other water sources.Methodology/Principal FindingsA quasi-experimental study with two concurrent cohorts was developed in two rural municipalities of the semiarid region of Brazil. A sample of 664 children, aged between 4 months and 5 years old, was followed up, of which 332 had access to rainwater cisterns (cistern group) and 332 did not, having water supplied from alternative sources (comparison group). In a period of approximately one year (2010) intestinal parasites were investigated in feces three times. The prevalence of G. duodenalis in children from the cistern group ranged from 4.8 to 10.5%, while the prevalence in the comparison group ranged from 7.6 to 16.7%. Multivariate analysis (GEE) showed a higher risk of G. duodenalis infection in children who did not have access to rainwater cisterns, when compared to children who did (OR 1.72; 95% CI 1.14–2.59). The other variables associated with G. duodenalis infection were: number of rooms per house (OR 0.89; 95% CI 0.80–0.99); family income (OR0.48; 95% CI 0.26–0.88); birth order (OR 1.72; 95% CI 1.17–2.51); preterm children (OR 1.70; 95% CI 1.19–2.43); and improper hand hygiene prior to food preparation (OR 4.78; 95% CI 1.95–11.76).Conclusions/SignificanceOwnership of a rainwater cistern is associated with a lower prevalence of G. duodenalis infection in children after adjustment for environmental and family-related factors. Nevertheless, the study suggests the necessity to complement physical interventions with actions related to personal and domestic hygiene to enable further reductions in parasite infections affecting mainly the underprivileged populations.

A review on physicochemical and microbiological contamination of roof-harvested rainwater in urban areas

“…An example of this can be found in studies related to rural Thailand where the bacterial contamination of shallow well water was higher than that of harvested rainwater (Wirojanagud et al, 1989;Pinfold et al, 1993). This is also the case of the Semi Arid region of Brazil, where the use of rainwater cisterns for drinking purposes has been associated with a decreased occurrence of diarrhea (Marcynuk et al, 2013) and Giardia duodenalis (Fonseca et al, 2014) among rural sparse communities. However, even though in general terms it has been reported that the gastrointestinal diseases in these communities tend to decrease with the use of rainwater, in those cases where rainwater storage lacked from hygiene both coliforms and parasites were detected (Xavier et al, 2011).…”

Improving Water Access and Health through Rainwater Harvesting: Perceptions of an Indigenous Community in Jalisco, Mexico

“…The data was reorganized to obtain the number of monthly cases because the doctor was only present in the community for 20 days per month. For statistical analyses, the data were grouped into four age groups: children (0-9 years old), young people (10)(11)(12)(13)(14)(15)(16)(17)(18)(19), adults (20-65) and the elderly (≥65), and by gender.…”

“…Although rainwater is recognized as a potential source for water use and consumption, the health impacts (positively or not) of consuming rainwater are not fully understood. Many factors are related to the health of human populations that use rainwater as a source of drinking water in rural and urban contexts [13,14] and few studies have been conducted to assess changes in health associated with the consumption of rainwater, especially in Latin America [14][15][16]. In Mexico, for example, there has been little investigation of the impact of RWHSs, including in rural, indigenous communities such as the one highlighted in this article.…”

“…Children (0-9 years old), 2. Young people(10)(11)(12)(13)(14)(15)(16)(17)(18)(19), 3. Adults (20-65), and 4.…”

Comportamento de dispositivos de desvio das primeiras águas de chuva como barreiras sanitárias para proteção de cisternas

“…Embora seja um importante programa que promove igualdade social entre as famílias beneficiadas, é essencial que se garanta o fornecimento de água sanitariamente segura. Segundo Fonseca et al (2014), cada família recebe uma cisterna com capacidade de armazenamento de 16.000 litros de água, que é indicado como suficiente para abastecer uma família de cinco pessoas durante a estação seca, considerando que a água seja utilizada para beber, cozinhar e escovar os dentes.…”