Ceramic water filters impregnated with silver nanoparticles as a point-of-use water-treatment intervention for HIV-positive individuals in Limpopo Province, South Africa: a pilot study of technological performance and human health benefits. J Water Health. 2014 Jun.

Abebe LS, et al.

Waterborne pathogens present a significant threat to people living with the human immunodeficiency virus (PLWH). This study presents a randomized, controlled trial that evaluates whether a household-level ceramic water filter (CWF) intervention can improve drinking water quality and decrease days of diarrhea in PLWH in rural South Africa. Seventy-four participants were randomized in an intervention group with CWFs and a control group without filters. Participants in the CWF arm received CWFs impregnated with silver nanoparticles and associated safe-storage containers. Water and stool samples were collected at baseline and 12 months. Diarrhea incidence was self-reported weekly for 12 months.

The average diarrhea rate in the control group was 0.064 days/week compared to 0.015 days/week in the intervention group (p < 0.001, Mann-Whitney). Median reduction of total coliform bacteria was 100% at enrollment and final collection. CWFs are an acceptable technology that can significantly improve the quality of household water and decrease days of diarrhea for PLWH in rural South Africa.

Safety of packaged water distribution limited by household recontamination in rural Cambodia. J Water Health. 2014 Jun.

Holman EJ, Brown J.

Packaged water treatment schemes represent a growing model for providing safer water in low-income settings, yet post-distribution recontamination of treated water may limit this approach. This study evaluates drinking water quality and household water handling practices in a floating village in Tonlé Sap Lake, Cambodia, through a pilot cross-sectional study of 108 households, approximately half of which used packaged water as the main household drinking water source.

We hypothesized that households purchasing drinking water from local packaged water treatment plants would have microbiologically improved drinking water at the point of consumption. We found no meaningful difference in microbiological drinking water quality between households using packaged, treated water and those collecting water from other sources, including untreated surface water, however.

Households’ water storage and handling practices and home hygiene may have contributed to recontamination of drinking water. Further measures to protect water quality at the point-of-use may be required even if water is treated and packaged in narrow-mouthed containers.

Business model innovation in the water sector in developing countries. Sci Total Environ. 2014 Aug

Gebauer H, et al.

Various technologies have been deployed in household devices or micro-water treatment plants for mitigating fluoride and arsenic, and thereby provide safe and affordable drinking water in low-income countries. While the technologies have improved considerably, organizations still face challenges in making them financially sustainable. Financial sustainability questions the business models behind these water technologies.

This article makes three contributions to business models in the context of fluoride and arsenic mitigation. Firstly, we describe four business models: A) low-value devices given away to people living in extreme poverty, B) high-value devices sold to low-income customers, C) communities as beneficiaries of micro-water treatment plants and D) entrepreneurs as franchisees for selling water services and highlight the emergence of hybrid business models.

Secondly, we show current business model innovations such as cost transparency & cost reductions, secured & extended water payments, business diversification and distribution channels.

Thirdly, we describe skills and competencies as part of capacity building for creating even more business model innovations. Together, these three contributions will create more awareness of the role of business models in scaling-up water treatment technologies.

Assessing the impact of drinking water and sanitation on diarrhoeal disease in low-and middle-income settings: systematic review and meta-regression. Trop Med Intl Health, May 2014.

Jennyfer Wolf, et al.

Objective - To assess the impact of inadequate water and sanitation on diarrhoeal disease in low- and middle-income settings.

Methods - The search strategy used Cochrane Library, MEDLINE & PubMed, Global Health, Embase and BIOSIS supplemented by screening of reference lists from previously published systematic reviews, to identify studies reporting on interventions examining the effect of drinking water and sanitation improvements in low- and middle-income settings published between 1970 and May 2013. Studies including randomised controlled trials, quasi-randomised trials with control group, observational studies using matching techniques and observational studies with a control group where the intervention was well defined were eligible. Risk of bias was assessed using a modified Ottawa–Newcastle scale. Study results were combined using meta-analysis and meta-regression to derive overall and intervention-specific risk estimates.

Results - Of 6819 records identified for drinking water, 61 studies met the inclusion criteria, and of 12 515 records identified for sanitation, 11 studies were included. Overall, improvements in drinking water and sanitation were associated with decreased risks of diarrhoea. Specific improvements, such as the use of water filters, provision of high-quality piped water and sewer connections, were associated with greater reductions in diarrhoea compared with other interventions.

Conclusions - The results show that inadequate water and sanitation are associated with considerable risks of diarrhoeal disease and that there are notable differences in illness reduction according to the type of improved water and sanitation implemented.

Assessing point-of-use ultraviolet disinfection for safe water in urban developing communities. Journal of Water and Health In Press, 2014.

Christina K. Barstow, Aaron D. Dotson and Karl G. Linden

Residents of urban developing communities often have a tap in their home providing treated and sometimes filtered water but its microbial quality cannot be guaranteed. Point-of-use (POU) disinfection systems can provide safe drinking water to the millions who lack access to clean water in urban communities. While many POU systems exist, there are several concerns that can lead to low user acceptability, including low flow rate, taste and odor issues, high cost, recontamination, and ineffectiveness at treating common pathogens.

An ultraviolet (UV) POU system was constructed utilizing developing community-appropriate materials and simple construction techniques based around an inexpensive low-wattage, low pressure UV bulb. The system was tested at the bench scale to characterize its hydrodynamic properties and microbial disinfection efficacy. Hydraulically the system most closely resembled a plug flow reactor with minor short-circuiting. The system was challenge tested and validated for a UV fluence of 50 mJ/cm2 and greater, over varying flow rates and UV transmittances, corresponding to a greater than 4 log reduction of most pathogenic bacteria, viruses, and protozoa of public health concern.

This study presents the designed system and testing results to demonstrate the potential architecture of a low-cost open-source UV system for further prototyping and field-testing.

Am J Trop Med Hyg. 2014 May 19.

Water Filter Provision and Home-Based Filter Reinforcement Reduce Diarrhea in Kenyan HIV-Infected Adults and Their Household Members.

Authors: Pavlinac PB, Naulikha JM, et al.

Among human immunodeficiency virus (HIV) -infected adults and children in Africa, diarrheal disease remains a major cause of morbidity and mortality. We evaluated the effectiveness of provision and home-based reinforcement of a point-of-use water filtration device to reduce diarrhea among 361 HIV-infected adults in western Kenya by comparing prevalence of self-reported diarrhea before and after these interventions. After provision of the filter, 8.7% of participants reported diarrhea compared with 17.2% in the 3 months before filter provision (odds ratio [OR] = 0.39, 95% confidence interval [95% CI] = 0.23-0.66, P < 0.001).

The association was similar among 231 participants who were already taking daily cotrimoxazole prophylaxis before being given a filter (OR = 0.47, 95% CI = 0.25-0.88, P = 0.019). Educational reinforcement was also associated with a modest reduction in self-reported diarrhea (OR = 0.50, 95% CI = 0.20-0.99, P = 0.047). Provision and reinforcement of water filters may confer significant benefit in reducing diarrhea among HIV-infected persons, even when cotrimoxazole prophylaxis is already being used.​

Estimation of Acute Diarrhea and Acute Respiratory Infections among Children under Five Years Who Lived in a Peri-urban Environment of Myanmar. OSIR, December 2013, Volume 6, Issue 4, p. 13-18.

Authors: Su Latt Tun Myint, KhinThet W, Khaymar M, PhyuSin A, Aye YM

Exposures to multiple environmental contaminants place children under five years of age at a greater risk to acute diarrhea and acute respiratory tract infections (ARI). To assess this phenomenon, a cross-sectional survey was conducted to examine relationships between environmental conditions and occurrence of acute diarrhea and ARI in peri-urban areas of Yangon Region, Myanmar. Mothers or caretakers of 620 children under five years were interviewed using a structured questionnaire. Of these children, 1% had acute diarrhea only, 45% had ARI only and 3.7% had both conditions during last four weeks.

Children suffered from acute diarrhea were 2.1 times more likely to suffer ARI in age group of 24-59 months (stratum-specific odds ratio = 2.1, 95% CI = 0.7-6.5). Multivariate analyses identified that bamboo housing and unsafe method of waste disposal were significantly associated with occurrence of acute diarrhea. However, no significant association was identified between ARI attack rate and environmental factors such as house condition and ventilation. Integrated community-based strategies to improve environmental conditions, water, sanitation and hygiene should be considered to reduce the dual burden of these illnesses in children under five years.

Below are abstracts to ten 2014 studies that were authored or co-authored by Jamie Bartram as of May 2014. We will do similar searches for the latest studies by Stephen Luby, Jay Graham, Thomas Clasen, Oliver Cumming, Pavani Ram and other key WASH authors.

1. Trop Med Int Health. 2014 May 8. Global assessment of exposure to faecal contamination through drinking water based on a systematic review. Bain R, Cronk R, Hossain R, Bonjour S, Onda K, Wright J, Yang H, Slaymaker T, Hunter P, Prüss-Ustün A, Bartram J.

OBJECTIVES: To estimate exposure to faecal contamination through drinking water as indicated by levels of Escherichia coli (E. coli) or thermotolerant coliform (TTC) in water sources.

METHODS: We estimated coverage of different types of drinking water source based on household surveys and censuses using multilevel modelling. Coverage data were combined with water quality studies that assessed E. coli or TTC including those identified by a systematic review (n = 345). Predictive models for the presence and level of contamination of drinking water sources were developed using random effects logistic regression and selected covariates. We assessed sensitivity of estimated exposure to study quality, indicator bacteria and separately considered nationally randomised surveys.

RESULTS: We estimate that 1.8 billion people globally use a source of drinking water which suffers from faecal contamination, of these 1.1 billion drink water that is of at least ‘moderate’ risk (>10 E. coli or TTC per 100 ml). Data from nationally randomised studies suggest that 10% of improved sources may be ‘high’ risk, containing at least 100 E. coli or TTC per 100 ml. Drinking water is found to be more often contaminated in rural areas (41%, CI: 31%-51%) than in urban areas (12%, CI: 8-18%), and contamination is most prevalent in Africa (53%, CI: 42%-63%) and South-East Asia (35%, CI: 24%-45%). Estimates were not sensitive to the exclusion of low quality studies or restriction to studies reporting E. coli.

CONCLUSIONS: Microbial contamination is widespread and affects all water source types, including piped supplies. Global burden of disease estimates may have substantially understated the disease burden associated with inadequate water services.

2. Trop Med Int Health. 2014 May 8. Assessing the impact of drinking water and sanitation on diarrhoeal disease in low- and middle-income settings: systematic review and meta-regression. Wolf J, Prüss-Ustün A, Cumming O, Bartram J, Bonjour S, Cairncross S, Clasen T, Colford JM Jr, Curtis V, De France J, Fewtrell L, Freeman MC, Gordon B, Hunter PR, Jeandron A, Johnston RB, Mäusezahl D, Mathers C, Neira M, Higgins JP.

OBJECTIVE: To assess the impact of inadequate water and sanitation on diarrhoeal disease in low- and middle-income settings.

METHODS: The search strategy used Cochrane Library, MEDLINE & PubMed, Global Health, Embase and BIOSIS supplemented by screening of reference lists from previously published systematic reviews, to identify studies reporting on interventions examining the effect of drinking water and sanitation improvements in low- and middle-income settings published between 1970 and May 2013. Studies including randomised controlled trials, quasi-randomised trials with control group, observational studies using matching techniques and observational studies with a control group where the intervention was well defined were eligible. Risk of bias was assessed using a modified Ottawa-Newcastle scale. Study results were combined using meta-analysis and meta-regression to derive overall and intervention-specific risk estimates.

RESULTS: Of 6819 records identified for drinking water, 61 studies met the inclusion criteria, and of 12 515 records identified for sanitation, 11 studies were included. Overall, improvements in drinking water and sanitation were associated with decreased risks of diarrhoea. Specific improvements, such as the use of water filters, provision of high-quality piped water and sewer connections, were associated with greater reductions in diarrhoea compared with other interventions.

CONCLUSIONS: The results show that inadequate water and sanitation are associated with considerable risks of diarrhoeal disease and that there are notable differences in illness reduction according to the type of improved water and sanitation implemented.

3.PLoS Med. 2014 May 6. Fecal contamination of drinking-water in low- and middle-income countries: a systematic review and meta-analysis. Bain R, Cronk R, Wright J, Yang H2, Slaymaker T, Bartram J.

BACKGROUND: Access to safe drinking-water is a fundamental requirement for good health and is also a human right. Global access to safe drinking-water is monitored by WHO and UNICEF using as an indicator “use of an improved source,” which does not account for water quality measurements. Our objectives were to determine whether water from “improved” sources is less likely to contain fecal contamination than “unimproved” sources and to assess the extent to which contamination varies by source type and setting.

METHODS AND FINDINGS: Studies in Chinese, English, French, Portuguese, and Spanish were identified from online databases, including PubMed and Web of Science, and grey literature. Studies in low- and middle-income countries published between 1990 and August 2013 that assessed drinking-water for the presence of Escherichia coli or thermotolerant coliforms (TTC) were included provided they associated results with a particular source type. In total 319 studies were included, reporting on 96,737 water samples. The odds of contamination within a given study were considerably lower for “improved” sources than “unimproved” sources (odds ratio [OR] = 0.15 [0.10-0.21], I2 = 80.3% [72.9-85.6]). However over a quarter of samples from improved sources contained fecal contamination in 38% of 191 studies. Water sources in low-income countries (OR = 2.37 [1.52-3.71]; p<0.001) and rural areas (OR = 2.37 [1.47-3.81] p<0.001) were more likely to be contaminated. Studies rarely reported stored water quality or sanitary risks and few achieved robust random selection. Safety may be overestimated due to infrequent water sampling and deterioration in quality prior to consumption.

CONCLUSION: Access to an “improved source” provides a measure of sanitary protection but does not ensure water is free of fecal contamination nor is it consistent between source types or settings. International estimates therefore greatly overstate use of safe drinking-water and do not fully reflect disparities in access. An enhanced monitoring strategy would combine indicators of sanitary protection with measures of water quality. Please see later in the article for the Editors’ Summary.

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A Quantitative Assessment Method for Ascaris Eggs on Hands. PLoS One, May 2014.

Authors: Aurelie Jeandron, et al.

The importance of hands in the transmission of soil transmitted helminths, especially Ascaris and Trichuris infections, is under-researched. This is partly because of the absence of a reliable method to quantify the number of eggs on hands. Therefore, the aim of this study was to develop a method to assess the number of Ascaris eggs on hands and determine the egg recovery rate of the method. Under laboratory conditions, hands were seeded with a known number of Ascaris eggs, air dried and washed in a plastic bag retaining the washing water, in order to determine recovery rates of eggs for four different detergents (cationic [benzethonium chloride 0.1% and cetylpyridinium chloride CPC 0.1%], anionic [7X 1% - quadrafos, glycol ether, and dioctyl sulfoccinate sodium salt] and non-ionic [Tween80 0.1% -polyethylene glycol sorbitan monooleate]) and two egg detection methods (McMaster technique and FLOTAC).

A modified concentration McMaster technique showed the highest egg recovery rate from bags. Two of the four diluted detergents (benzethonium chloride 0.1% and 7X 1%) also showed a higher egg recovery rate and were then compared with de-ionized water for recovery of helminth eggs from hands. The highest recovery rate (95.6%) was achieved with a hand rinse performed with 7X 1%. Washing hands with de-ionized water resulted in an egg recovery rate of 82.7%. This washing method performed with a low concentration of detergent offers potential for quantitative investigation of contamination of hands with Ascaris eggs and of their role in human infection. Follow-up studies are needed that validate the hand washing method under field conditions, e.g. including people of different age, lower levels of contamination and various levels of hand cleanliness.

Filters for the World: POU filters provide clean water for developing nations | Source/complete article: by Lieselotte Heederik, March 2014 |

This article provides an overview on Point-of Use water filters and gives information on the Nazava water filter. The Nazava filter is new product has recently been introduced on the market in Indonesia. Nazava water filters use a simple ceramic filter shaped like a soda can. The ceramic is impregnated with silver and filled with activated carbon, which helps improve the water’s taste. The filter’s small size makes it easy to transport, and, as its costs per liter are three times cheaper than boiling water and nine times cheaper than bottled water, the economic benefits are high.  

Nazava filters have 99.99% effective bacterial removal. They have been tested in 16 laboratories in Indonesia and overseas. They comply with Indonesian standards for safe drinking water and WHO guidelines for bacteria removal.9 To address the preferences of every household, the filters come in different sizes and colors.

Nazava filters can make well, rain and tap water drinkable without boiling it first. As no fuel wood is needed, they reduce the labor burden on women. Using them also can result in significant savings in gas and kerosene. They purify turbid water as well, as long as the water is fresh.