Comparing Microbial Water Quality in an Intermittent and Continuous Piped Water Supply

July 8, 2013 · 0 comments

Water Research, 11 June 2013

Comparing Microbial Water Quality in an Intermittent and Continuous Piped Water Supply

Emily Kumpel, et al.

Highlights
• Water quality was compared in an intermittent and continuous distribution system.
• Indicator bacteria were detected at higher concentrations in intermittent taps.
• A higher percentage of samples from continuous taps met free chlorine guidelines.
• There was evidence of intrusion in the intermittent distribution network.
• Drinking water stored in households with continuous supply became recontaminated.

Supplying piped water intermittently is a common practice throughout the world that increases the risk of microbial contamination through multiple mechanisms. Converting an intermittent supply to a continuous supply has the potential to improve the quality of water delivered to consumers. To understand the effects of this upgrade on water quality, we tested samples from reservoirs, consumer taps, and drinking water provided by households (e.g. from storage containers) from an intermittent and continuous supply in Hubli-Dharwad, India, over one year. Water samples were tested for total coliform, E. coli, turbidity, free chlorine, and combined chlorine. While water quality was similar at service reservoirs supplying the continuous and intermittent sections of the network, indicator bacteria were detected more frequently and at higher concentrations in samples from taps supplied intermittently compared to those supplied continuously (p<0.01).

Detection of E. coli was rare in continuous supply, with 0.7% of tap samples positive, compared to 31.7% of intermittent water supply tap samples positive for E. coli. In samples from both continuously and intermittently supplied taps, higher concentrations of total coliform were measured after rainfall events. While source water quality declined slightly during the rainy season, only tap water from intermittent supply had significantly more indicator bacteria throughout the rainy season compared to the dry season. Drinking water samples provided by households in both continuous and intermittent supplies had higher concentrations of indicator bacteria than samples collected directly from taps. Most households with continuous supply continued to store water for drinking, resulting in re-contamination, which may reduce the benefits to water quality of converting to continuous supply.

More than a Drop in the Bucket: Decentralized Membrane-Based Drinking Water Refill Stations in Southeast Asia

July 8, 2013 · 1 comment

Environ. Sci. Technol., May 31, 2013

More than a Drop in the Bucket: Decentralized Membrane-Based Drinking Water Refill Stations in Southeast Asia

Laura C Sima and Menachem Elimelech

Decentralized membrane-based water treatment and refill stations represent a viable and growing business model in Southeast Asia, which rely upon the purchase of water from refill stations by consumers. This feature article discusses these water treatment and refill stations, including the appropriateness of the technology, the suitability of the business models employed, and the long-term environmental and operational sustainability of these systems. We also provide an outlook for the sector, highlighting key technical challenges that need to be addressed in order to improve the capacity of these systems, such that they can become an effective and financially viable solution to the clean water crisis.

Economic evaluation of social technologies applied to health promotion: water supply by the SODIS System

July 8, 2013 · 1 comment

Cien Saude Colet. 2013 Jul;18(7):2119-27.

[Economic evaluation of social technologies applied to health promotion: water supply by the SODIS System in riverside communities of the Brazilian Amazon]. [Article in Portuguese]

Lobo MA, Lima DM, Souza CM, Nascimento WA, Araújo LC, Santos NB.

The so-called social technologies have been widely used in many places around the world as a viable alternative for low-income populations to gain access to opportunities for employment and income and other aspects related to quality of life, including basic sanitation. This paper conducts a cost-benefit analysis of using a low cost technology for drinking water used in several countries, namely the SODIS system. The study was conducted in riverside communities living in the island area of Belem municipality, located in the Brazilian Amazon. Data were collected through questionnaires answered by families living on three islands: Jutuba, Nova and Urubuoca. The results were positive, considering the cost-benefit analysis of the project, which demonstrates the economic viability of using the SODIS system in the situation investigated.

Characteristics and the potential effectiveness of a household water filter in the Republic of Kiribati

July 8, 2013 · 1 comment

Journal of Water, Sanitation and Hygiene for Development In Press, July 2013.

Assessing the demographic, behavioural and environmental characteristics and the potential effectiveness of a household water filter in the Republic of Kiribati

Rebecca Psutka, Patricia Priest, Tieren Davies, Teretia Rakunuea, Steven Iddings and Andre Reiffer

Department of Preventive and Social Medicine, University of Otago, New Zealand 9010
E-mail: rebecca.psutka@gmail.com
Ministry of Health and Medical Services, Republic of Kiribati
World Health Organization, Cambodia
World Health Organization, Republic of Kiribati

Aim: To measure diarrhoea burden, environmental hygiene and water quality in Kiribati, in order to assess whether a domestic water filter would be likely to improve child and community health.

Methods: Cross-sectional survey of randomly selected households using a questionnaire and analysis of drinking and source water samples.

Results: Female heads of 97 randomly selected households answered the questionnaire. One in four children younger than five years had experienced diarrhoea in the past month and 7% in the past week. Thirty-four percent of respondents and 57% of their children practised open defecation. Handwashing at important times was uncommon as was safe water storage. Almost all households usually boil water. Overall, drinking water was less contaminated than source water (p = 0.05). Where paired samples of source and drinking water were available, drinking water that had been boiled was significantly less contaminated than source water (1 tailed t-test; p = 0.014).

Conclusion: Both ‘waterwashed’ and waterborne transmission are likely responsible for diarrhoea. In this setting where nearly all households boil water, in the absence of hygiene and storage improvements, the substitution of a filter is unlikely to improve water quality.

Extra Food Means Nothing to Stunted Kids With Bad Water: Health

July 3, 2013 · 1 comment

Extra Food Means Nothing to Stunted Kids With Bad Water: Health | Source: Bloomberg, June 12, 2013

Aameena Mohammed gives her 20-month-old daughter Daslim Banu plenty to eat. The girl’s mother supplements breast milk with eggs, soup and rice to help her grow. The extra food doesn’t help. Daslim still weighs only as much as a healthy infant half her age.

Mohammed’s home, in one of the poorest districts of the south Indian city of Vellore, is among the 65 percent of India’s homes without running water and safe sewage disposal. Feces and urine collect next to the doorway in an open drain — the source of odor permeating the tin-roofed shack and of the microbes likely retarding the toddler’s growth.

Villagers collect water from a public water pipe in Nayakhera village, Maharashtra, India. Photographer: Sanjit Das/Bloomberg

Scientists increasingly suspect that constant exposure to bacteria, virus and parasite-laden fecal contaminants may be frustrating attempts to end malnutrition. In effect, the best diet-based measures to fight chronic hunger in the developing world are being negated by a failure to meet basic human needs: clean water and sanitation.

The problem exists not just in India. A quarter of children in developing countries are underweight, and malnutrition is the root cause of the deaths of more than 2 million children annually, according to the United Nations Children’s Fund inNew York. Worldwide, 870 million people are chronically hungry, almost all of them in developing countries.

“You really can’t address stunting unless you clean up the sanitary environment,” said Clarissa Brocklehurst, Unicef’s former chief of water, sanitation and hygiene, who worked in India from 1999 to 2001. “It doesn’t matter how much extra food you try to stick into kids or how much dietary supplements you give them, it will all just go through them.”

Stunted Children

Daslim, who runs about the home in an oversized red and green dress that hangs limply from her bony shoulders, has suffered at least five bouts of debilitating diarrhea in the past 10 months, and was hospitalized for three days with a high fever in September. In November, she weighed 7 kilograms (15 pounds) — about two-thirds the normal weight of a girl her age.

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A Stepped Wedge, Cluster-Randomized Trial of a Household UV-Disinfection and Safe Storage Drinking Water

July 3, 2013 · 1 comment

A Stepped Wedge, Cluster-Randomized Trial of a Household UV-Disinfection and Safe Storage Drinking Water Intervention in Rural Baja California Sur, Mexico. Am J Trop Med Hyg. 2013 Jun 3.

Gruber JS, et al.

Abstract - In collaboration with a local non-profit organization, this study evaluated the expansion of a program that promoted and installed Mesita Azul, an ultraviolet-disinfection system designed to treat household drinking water in rural Mexico. We conducted a 15-month, cluster-randomized stepped wedge trial by randomizing the order in which 24 communities (444 households) received the intervention. We measured primary outcomes (water contamination and diarrhea) during seven household visits.

The intervention increased the percentage of households with access to treated and safely stored drinking water (23-62%), and reduced the percentage of households with Escherichia coli contaminated drinking water (risk difference (RD): -19% [95% CI: -27%, -14%]). No significant reduction in diarrhea was observed (RD: -0.1% [95% CI: -1.1%, 0.9%]). We conclude that household water quality improvements measured in this study justify future promotion of the Mesita Azul, and that future studies to measure its health impact would be valuable if conducted in populations with higher diarrhea prevalence.

Provision of bednets and water filters to delay HIV-1 progression

July 3, 2013 · 1 comment

Provision of bednets and water filters to delay HIV-1 progression: cost-effectiveness analysis of a Kenyan multisite study. Trop Med Intl Health, May 2013.

Eli Kern, et al.

Objective – To estimate the effectiveness, costs and cost-effectiveness of providing long-lasting insecticide-treated nets (LLINs) and point-of-use water filters to antiretroviral therapy (ART)-naïve HIV-infected adults and their family members, in the context of a multisite study in Kenya of 589 HIV-positive adults followed on average for 1.7 years.

Methods – The effectiveness, costs and cost-effectiveness of the intervention were estimated using an epidemiologic-cost model. Model epidemiologic inputs were derived from the Kenya multisite study data, local epidemiological data and from the published literature. Model cost inputs were derived from published literature specific to Kenya. Uncertainty in the model estimates was assessed through univariate and multivariate sensitivity analyses.

Results – We estimated net cost savings of about US$ 26 000 for the intervention, over 1.7 years. Even when ignoring net cost savings, the intervention was found to be very cost-effective at a cost of US$ 3100 per death averted or US$ 99 per disability-adjusted life year (DALY) averted. The findings were robust to the sensitivity analysis and remained most sensitive to both the duration of ART use and the cost of ART per person-year.

Conclusions – The provision of LLINs and water filters to ART-naïve HIV-infected adults in the Kenyan study resulted in substantial net cost savings, due to the delay in the initiation of ART. The addition of an LLIN and a point-of-use water filter to the existing package of care provided to ART-naïve HIV-infected adults could bring substantial cost savings to resource-constrained health systems in low- and middle-income countries.

Are existing drinking water sources safe from As contamination in Hanam province, Vietnam?

July 1, 2013 · 1 comment

Are existing drinking water sources safe from As contamination in Hanam province, Vietnam? Geochemical Journal, Vol. 47 (No. 3), pp. 363-368, 2013.

Manh Cuong Do,1,2 Kyoung-Woong Kim,1 Dac Phu Tran,2 Duy Bao Nguyen,3 Mathuros Ruchirawat4 and Panida Navasumrit4
Author email: cuong_ytdp@yahoo.com

1School of Environmental Science and Engineering, Gwangju Institute of Science and Technology, Gwangju 500-712, Korea
2Health Environment Management Agency, Ministry of Health Vietnam, Hanoi, Vietnam
3National Institute of Occupational and Environmental Health, Hanoi, Vietnam
4Chulabhorn Research Institute, Bangkok 10210, Thailand

Abstract: This study investigated arsenic (As) concentrations in existing drinking water sources in Hanam province, Vietnam. Sand-filtered groundwater, piped water, raw groundwater, and a type of drinking water mostly sourced from rainwater (hereafter referred to as the “stored rainwater”) are commonly used for drinking purposes in this area. It was found that all water sources contained different levels of toxic As. The highest levels were found in raw groundwater, followed by sand-filtered water, piped water, and stored rainwater. More than 50% of the stored rainwater samples contained As levels above the WHO recommendation value. As such, the daily As uptake in local residents from this kind of stored rainwater may be larger than previously considered because they consume stored rainwater as an alternative drinking water source. Relatively high levels of As in the stored rainwater samples also suggested that residents possibly mix rain and groundwater in rainwater containers in order to meet their daily water demand.

Setting Research Priorities to Reduce Mortality and Morbidity of Childhood Diarrhoeal Disease in the Next 15 Years

June 25, 2013 · 1 comment

Setting Research Priorities to Reduce Mortality and Morbidity of Childhood Diarrhoeal Disease in the Next 15 Years. PLoS Med, May 2013.

Kerri Wazny, et al.

Excerpt:

The Disease Burden, Aetiology and Distribution team prioritized developing a clear understanding of the prevalence and distribution and risk factors of diarrhoea globally. Understanding long-term child development outcomes was a priority in the Nutrition and Long-Term Outcomes team, which emphasized a need for education for diarrhoea prevention and in promoting child development.

The Preventive Nutrition Strategies team highlighted the importance of community involvement and education regarding the relationship between ideal nutrition strategies and prevention of diarrhoea. The Emerging Interventions team also prioritised research questions regarding the importance of nutritional factors in diarrhoeal disease.

Both the Case Management team and the Monitoring and Evaluation team emphasized research priorities around ORS and zinc use, including determinants of use, factors that drive care-seeking behaviour, delivery strategies, and social marketing. The Monitoring and Evaluation team also prioritized finding factors that have led to decline in ORS use as well as defining attributes of successful and sustainable childhood diarrhoea programs.

In addition to placing an emphasis on ORS and zinc, the Other Innovations team’s highly ranked questions included research questions involving feeding practices during diarrhoea and research questions regarding hand washing and sanitation. The WASH Interventions team also prioritized hand washing, highlighting the importance of better understanding the relative contribution of different transmission routes to disease burden. The team identified a need to study the effectiveness of programs to improve sanitation, water supply and hygiene behaviour in the home and in schools, and to better understand the transmission routes of diarrhoea pathogens through the environment.

Setting priorities for development of emerging interventions against childhood diarrhoea

June 25, 2013 · 2 comments

Setting priorities for development of emerging interventions against childhood diarrhoea. Jnl Global Health, June 2013.

Zulfiqar A. Bhutta, et al.

An expert panel exercise was conducted to assess feasibility and potential effectiveness of 10 emerging health interventions against childhood diarrhoea. Twelve international experts were invited to take part in a CHNRI priority setting process. This group used 12 different criteria relevant to successful development and implementation of the emerging interventions, nine of which were retained in the final analysis.

They showed most collective optimism towards developing household or community-level water treatment, followed by sustainable, affordable latrine options; those two emerging interventions were followed by antibiotic therapy of Cryptosporidium diarrhoea, and oral or transcutaneous enteric vaccine development.

The second level of priority was assigned to probiotics and prebiotics; combination vaccine for Cryptosporidium, Shigella and enterotoxigenic Escherichia coli (ETEC); and to the use of anti-emetics in case management. The lowest level of enthusiasm was expressed towards the treatment or prevention (vaccines) of environmental enteropathy, CFTR inhibitors, and the inhibitors of intestinal epithelial secretion in the treatment of diarrhoea. The exercise suggested that there are relatively few novel or feasible interventions in the course of development to address the high residual disease burden of diarrhoea in children.

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