Monday, October 7, 2013

Automated chlorine dosers in Dhaka, Bangladesh

Article in Stanford Medicine Magazine by Ruthann Richter describing our work to design low-cost passive chlorination systems in Dhaka, Bangladesh:

Priming the Pumps: Debugging Dhaka's Water

Thursday, September 12, 2013

New study on household surface contamination and demand for disinfection products

Short Report: Fecal Indicator Bacteria Contamination of Fomites and Household Demand for Surface Disinfection Products: A Case Study from Peru

Online preview: American Journal of  Tropical Medicine and Hygiene

by Timothy R. Julian, Luke H. MacDonald, Yayi Guo, Sara J. Marks, Margaret Kosek, Pablo P. Yori, Silvia Rengifo Pinedo, and Kellogg J. Schwab

Surface-mediated disease transmission is understudied in developing countries, particularly in light of the evidence that surface concentrations of fecal bacteria typically exceed concentrations in developed countries by 10- to 100-fold. In this study, we examined fecal indicator bacterial contamination of dinner plates at 21 households in four peri-urban communities in the Peruvian Amazon. We also used surveys to estimate household use of and demand for surface disinfectants at 280 households. Despite detecting total coliform, enterococci, and Escherichia coli on 86%, 43%, and 24% of plates sampled, respectively, less than one-third of households were regularly using bleach to disinfect surfaces. Among non-users of bleach, only 3.2% of respondents reported a new demand for bleach, defined as a high likelihood of using bleach within the next year. This study highlights the potential for marketing approaches to increase use of and demand for surface disinfectants to improve domestic hygiene.

Wednesday, June 12, 2013

Taking stock of the humble handpump

There seems to be much discussion about handpumps in my email inbox these days.  Considering how ubiquitous they are across rural landscapes globally, we know surprisingly little about the common handpump.  For example, how many handpumps are installed on the African continent, and of these how many are actually functioning?  What sort of designs exist and where are they typically used?  Which countries promote a standard design and which do not?  It's tedious work compiling and crunching the numbers, but taking stock of the infrastructure is critical if we are to make the most of the next generation of water supply investments.  This is especially true for initiatives that aim to improve the sustainability of non-networked water sources, since we do at least know that they fail and fail often.

Here are a few ways that you can contribute to improving our collective understanding of handpumps:

The Rural Water Supply Network (RWSN) invites water practitioners to take an online survey about recent experiences with handpumps and priorities for the sector going forward.

Also at RWSN, Sean Furey is working on updating their handpump functionality statistics from 2009--perhaps one of the most cited data sources for those working on sustainability of water supplies!  Data can be emailed to him in excel format at sean.furey (at)  Note that partial or imperfect data sets are welcome and will receive the appropriate caveats in the final presentation, and all data sources will be acknowledged.  More info in the May newsletter.

At Oxford University, Jessica MacArthur is investigating the effectiveness of handpump standardization policies and invites water professionals to voice their thoughts with this survey.  (Data will be shared publicly in September 2013).   

Wednesday, May 22, 2013

Burden and aetiology of diarrhoeal disease (GEMS)

Main findings from GEMS (the Global Enteric Multicenter Study) have just been published in the Lancet, along with a commentary. The GEMS study enrolled thousands of children with and without diarrhea from Kenya, Mali, Mozambique, The Gambia, Bangladesh, India, and Pakistan. The researchers found that most cases of moderate/severe diarrhea can be attributed to four pathogens: rotavirus, Shigella, cryptosporidium, and enterotoxigenic E. coli (ST-ETEC). Notably, at least one enteric pathogen was identified in the stool of 72% of control children (compared to 83% of cases), suggesting high prevalence of asymptomatic infections. Co-infection was also common, with two or more pathogens detected in 45% of cases and 31% of control children.  

The release is also covered in The New York Times:

GLOBAL HEALTH: 4 Germs Cause Most of Infants’ Severe Diarrhea

A study pinpoints just four microbes as the most common causes of
severe and fatal diarrhea among the world’s infants.

Monday, May 20, 2013

Sanitation in the Literature - May 20

Your semi-erratic-but-maybe-weekly-someday literature round-up on Sanitation, Courtesy of PipesAndPotties.

Any all comments are appreciated!

Factors associated with breastfeeding in two municipalities with low human development index in Northeast Brazil.
Mothers with better socioeconomic conditions, as represented by education, sanitation, and possession of consumer goods, had a higher median duration of exclusive/ predominant breastfeeding in both towns.

Determinants of reduced child stunting in Cambodia: analysis of pooled data from three Demographic and Health Surveys.
The reduction in stunting prevalence during the past decade was attributable to improvements in household wealth, sanitation, parental education, birth spacing and maternal tobacco use. The prevalence of stunting would have been further reduced by scaling up the coverage of improved sanitation facilities, extending birth intervals, and eradicating maternal tobacco use.

Are constructed treatment wetlands sustainable sanitation solutions?
Constructed treatment wetlands meet the basic criteria of sustainable sanitation systems by preventing diseases, protecting the environment, and being an affordable, acceptable, and simple technology. Additionally, constructed treatment wetlands produce treated wastewater of high quality, which is fostering reuse, which in turn makes them applicable in resources-oriented sanitation systems. The paper discusses the features that make constructed treatment wetlands a suitable solution in sustainable resources-oriented sanitation systems, the importance of system thinking for sustainability, as well as key factors for sustainable implementation of constructed wetland systems.

Faecal sludge management with the larvae of the black soldier fly (Hermetia illucens) - From a hygiene aspect.
 For example, grown larvae of the black soldier fly, Hermetia illucens L. (Diptera: Stratiomyidae), make an excellent protein source in animal feed, while the feeding activity of the larvae substantially reduces the dry mass of the treated material. This study examined the effect of black soldier fly larvae on the concentration of pathogenic microorganisms in human faeces and found a 6 log10 reduction in Salmonella spp. in human faeces in eight days, compared with a <2 log10 reduction in the control.

Land application of manure and Class B biosolids: an occupational and public quantitative microbial risk assessment.
Comparison of risks by pathogen group confirmed greater bacterial risks from manure, whereas viral risks were exclusive to biosolids. A direct comparison of the two residual types showed that biosolids use had greater risk because of the high infectivity of viruses, whereas the presence of environmentally recalcitrant pathogens such as and maintained manure risk. Direct comparisons of shared pathogens resulted in greater manure risks. Overall, it appears that in the short term, risks were high for both types of residuals, but given treatment, attenuation, and dilution, risks can be reduced to near-insignificant levels.

Monday, May 13, 2013

Sanitation in the Literature - May 6 through May 13

The following research articles from the previous week caught my attention.  Weigh in if you have any thoughts on any of them, or saw something this past week I missed.

Assessment of village water and sanitation committee in a district of Tamil Nadu, India.
"A descriptive study was conducted among 75 members of five Village Water and Sanitation Committees (VWSCs) and 15 local residents in Tamil Nadu, India to assess committee's formation and decision making process.... Although, all of them were aware about presence of guidelines, none of them knew its contents. About 20% opined that meetings were not being conducted regularly. All members said that they had problems in attending meeting regularly, take decisions if at least 10 (67%) members are present and fund was not adequate for 1 year period. One-third of local residents did not know the committee formation process and none of them aware about guidelines."

Food safety knowledge and practices of abattoir and butchery shops and the microbial profile of meat in Mekelle City, Ethiopia.
"15.4% of the abattoir workers had no health certificate and there was no hot water, sterilizer and cooling facility in the abattoir. 11.3% of the butchers didn't use protective clothes. There was a food safety knowledge gap within the abattoir and butcher shop workers. The mean values of bacterial load of abattoir meat, butcher shops and street meat sale was found to be 1.1×10(5), 5.6×10(5) and 4.3×10(6) cfu/g, respectively. The major bacterial pathogens isolated were Escherichia coli, Staphylococcus aureus and Bacillus cereus."

Cooking fuel choices and garbage burning practices as determinants of birth weight: a cross-sectional study in Accra, Ghana.
"Maternal use of charcoal as a cooking fuel during pregnancy and burning of garbage at home are strong determinants of average fetal growth and risk of LBW. Efforts to reduce maternal exposures to IAP are thus important to improve birth outcomes."

School toilets: facilitating hand hygiene? A review of primary school hygiene facilities in a developed country.
"Nineteen schools (28%) followed the New Zealand Ministry of Education Code of Practice for toilet and bathroom facilities in schools, by providing warm water, liquid soap at every basin and functioning hand drying facilities. A further 25 schools (37%) would have met the standards except they provided only cold water (21 schools) or the cloth roller towels were unusable (4 schools). The other 24 schools' toilet facilities were deficient in some way, including one with no soap and six that provided no drying facilities. School socioeconomic position and toilet facility quality were not related."

Wednesday, April 17, 2013

Sanitation in the News - Week of April 10-17.

Here are some relevant popular press articles on sanitation from the past seven days, give or take.  Presented without comment, so please feel free to comment yourselves below.

"Zoom Alliance, a subsidiary of Zoomlion Ghana Limited in partnership with the Ministry for Local Government and Rural Development and the Accra Metropolitan Assembly will soon introduce a Community Sanitation Police and Monitoring Taskforce to help curb poor sanitation in the country...The move according to Kenneth Asare is aimed at ensuring that flooding and issues of malaria and cholera outbreaks during rainy seasons are eliminated"

Investing in Latin America's Water and Sanitation Solutions
"we’re left with a lot of work to do to reach the ultimate goal of universal access to clean water and improved sanitation. For the past three years, two early-stage social enterprises in South America—TOHL in Chile andX-Runner in Peru—have been hard at work creating the means to get us there."

Switzerland Gives $6 Million for Water, Sanitation in Zimbabwe
 "...Nkomo spoke after Switzerland gave $6 million to UNICEF to improve Zimbabwe's rural water supply and sanitation.  But given that 75 percent of Zimbabwe’s rural population does not have access to clean water, that money may just be a figurative drop in the ocean. ..."

Nottingham researcher hopes sanitation app will help cut diseases in poor areas
"Mr Iliffe, a doctoral researcher at the university’s Horizon Digital Economy Research Institute, has created a new web and mobile app, called Taarifa....It allows people to input and share their own sanitation problems using text messaging, e-mail or social media. The reports can be monitored by local authorities and acted upon to carry out repairs, improvements or new infrastructure, giving citizens the power to affect changes in their own communities..."

Gov’ts Can Make Water and Sanitation for All Africans a Reality by 2030; Says WaterAid

WaterAid’s report ‘Everyone Everywhere’ launched today(1) by President Johnson Sirleaf at a UN event on water in the Hague, in the Netherlands, sets out a vision for making safe water and sanitation available to all and reviews the progress that has been made to date in tackling water and sanitation poverty.

Sanitation: FCT residents applaud role of waste collectors

The residents told the News Agency of Nigeria (NAN) in Abuja that water  vendors, known as Mairuwa, and waste collectors, called Maishara, provided essential services, such as water supply and waste collection.

African Water Facility Launches the Fostering Innovative Sanitation and Hygiene in Monrovia Project

"The Facility offers a €1.2-million grant to the Monrovia City Corporation (MCC) to support a project aimed at increasing access to sustainable and affordable sanitation and hygiene services to over 800,000 urban slum-dwellers in Monrovia, Liberia.  This will be the first initiative by the Government to provide fecal sludge management services to unsewered poor areas of Liberia since the end of the civil war in 2003....The AWF grant will cover 86 per cent of the cost involved in the implementation of an effective, efficient and sustainable fecal sludge management system, which will include the construction and rehabilitation of sanitation infrastructure, as well as the production of affordable crop fertilizer from the fecal sludge collected."

"Sesame Workshop, the non-profit educational organization behind Sesame Street, announced today that it is receiving funding from the Bill & Melinda Gates Foundation to promote hygiene and sanitation among children and families in high-needs areas in Bangladesh, India and Nigeria."

Saudis Approve More Water, Sewage Projects Across Kingdom

"Saudi Arabia approved $96 million of water and sanitation projects including reservoirs across the kingdom, state-owned Saudi Press Agency reported, citing Minister of Water and Electricity Abdullah Al-Hussayen."

"Thames Water’s Clive Dickens is overseeing the WaterAid charity’s four-year project now half-way through which has so far fitted clean supplies and sanitation in four villages that the company has ‘adopted’.  Around 13,000 villagers are now getting safe water to drink and hygienic sanitation."

Monday, April 15, 2013

Sanitation Articles Published 7-15 April 2013

There's been a few new articles on sanitation published in the past week or so.  Titles and excerpts from abstracts to a handful of them:

Knowledge, awareness and practice of the importance of hand-washing amongst children attending state run primary schools in rural Malawi.
"The study determined: (1) presence of Escherichia coli on the hands of 126 primary school pupils, (2) knowledge, awareness and hygiene practices amongst pupils and teachers and (3) the school environment through observation. Pupil appreciation of hygiene issues was reasonable; however, the high percentage presence of E. coli on hands (71%) and the evidence of large-scale open defaecation in school grounds revealed that apparent knowledge was not put into practice. The standard of facilities for sanitation and hygiene did not significantly impact on the level of knowledge or percentage of school children's hands harbouring faecal bacteria. Evidence from pupils and teachers indicated a poor understanding of principles of disease transmission. Latrines and hand-washing facilities constructed were not child friendly."

Outbreak of Cholera in Tilathi VDC Saptari Nepal.
"Descriptive epidemiology suggested the clustering of cases were around the pond where they clean utensils, take bath and wash clothes. The Vibrio cholerae 01 El Tor, Ogawa serotype was isolated in 03 out of 05 suspected stool samples and in all three of the pond water samples. They reported that most of the houses do not have the toilet and people do not wash their hands regularly with soap and water after defecation. "

Prevalence and Determinants of Micronutrient Deficiencies among Rural Children of Eight States in India.
" A community-based cross-sectional study was carried out by adopting a multistage stratified random sampling procedure...  preschool children were included for ocular signs...hemoglobin, and ..iodine deficiency disorders.... Micronutrient malnutrition is a public health problem among rural children, and it was higher among children of SC/ST, illiterate parents and those not possessing a sanitary latrine. Thus, there is a need to improve environmental sanitation; fortification of foods could also help in mitigating the problem."

Pilot project of the Nutrition-Friendly School Initiative (NFSI) in Ouagadougou, Burkina Faso and Cotonou, Benin, in West Africa.
"This paper describes the first African experience with the Nutrition-Friendly School Initiative (NFSI) in two large West African cities: Ouagadougou, Burkina Faso and Cotonou, Benin. NFSI was launched by the World Health Organization (WHO) and its partners in 2006, as a means of preventing the double burden of malnutrition: the coexistence of undernutrition and overnutrition among school-children... The Project... fostered the installation of health and nutrition committees in selected schools, and helped with the initial school self-assessments... technical assistance and seminal funds were provided... [In addition,] training was given to street vendors in order to improve the hygiene and nutritional value of food sold to schoolchildren. Other activities included special nutrition events and sanitation measures. In both cities, NFSI showed promising results in terms of school and community mobilization towards improved nutrition and health; however ... household poverty and scarce school resources appear as major barriers to gaining full impact of NFSI in low-income populations."

Progress towards Millennium Development Goal 1 in northern rural Nicaragua: findings from a health and demographic surveillance site.
"Between 2004 and 2009, poverty was reduced as a number of interventions increased. Although microcredit was inequitably distributed across the population, combined with home gardening and technical training, it resulted in significant poverty reduction in this rural area."

Monday, March 11, 2013

Key Elements to Rigorous Program Evaluation

Purnima Menon spoke last week at Johns Hopkins Bloomberg School of Public Health on the early results of the Alive and Thrive initiative taking place in Bangladesh, Vietnam, and Ethiopia.  Dr. Menon works on the project in Bangladesh through her position as a Research Fellow at the International Food Policy Research Institute.

Alive and Thrive is a Bill and Melinda Gates Foundation supported initiative that is looking to improve infant and young child feeding practices through a combination of mass media, journalist advocacy, social mobilization, mother's forums, and home visits by front line and health care workers.

One of the topics that Dr. Menon discussed was a review she and her colleagues had done on defining the key elements to a rigorous program evaluation.  This review was essential because Alive and Thrive is not just about quantifying improvements in child health.  Alive and Thrive is also about identifying the factors that led to the success or failure of the program so that the program can be either scaled or improved.

Dr. Menon stated that there are four essential elements to rigorous program evaluation:
1) Pre and Post assessments of the intervention require a quantitative comparison with a control.  "The Double Difference Approach."
Showing that the study group who received an intervention is better off than they were before they received the intervention is not sufficient evidence.  You need an appropriate counterfactual group (a control group) that did not receive the intervention in order to show that the intervention works.

One example of where this is important is in the Alive and Thrive's finding a dramatic reduction in child stunting within the first few years.  The double difference approach is needed to determine whether or not this reduction is due to: 1) the intervention, or 2) improvements in food supply availability.

2) Rigor in Design
Randomization where possible is the gold standard in research design.  Randomization reduces chances of systematic bias.

3) Rigor in Measurement
The right indicators must be measured.  Data need to be collected on immediate drivers of the outcome, as well as contextual factors.  Finally, program exposures need to be captured.  That is, intervention efficacy is reliant on exposure of the population to the intervention.  A quantitative analysis of that exposure is needed to determine whether failures occur due to an ineffective intervention or failure to reach the target population.

4) Theory Driven Process Evaluation
When assessing whether or not an intervention works, you also need a theoretical framework for the mechanism by which the intervention works.  If you can evaluate the mechanism simultaneous to evaluating the outcome, you can the "why?" of whether or not the intervention was successful.  One recent example is from a study on HIV infections in women provided with pre-exposure prophalyaxis (PrEP) to prevent infection.  In the study, enrolled women claimed to be taking PrEP drugs and very few returned unused drugs.  However, blood work showed that the compliance among participants was actually low.  By including measurements of blood work, the researchers were able to identify the failure in the study.  Specifically, the researchers identified human behaviour, not drug efficacy, as the barrier to successful PrEP implementation.

Dr. Menon's overarching theme for this portion of her talk was that effort needs to be spent on program evaluation.  Furthermore, that effort should be just as rigorous (if not more so) as effort devoted to defining and implementing the programs in the first place.

Monday, March 4, 2013

Slum upgrading

A Cochrane review on the impact of slum upgrading was published last month, looking specifically at the impact of improving physical environments and infrastructure. The most common interventions were improvements in water supply, sanitation, drainage, roads, paved footpaths.

The main finding is a reduction in incidence of diarrhoea due to improved water connections, with mixed results on parasitic infections or other communicable diseases and insufficient evidence on many other impacts. They also call for involvement of independent researchers early on in implementation (since most studies found were post-hoc evaluations) and for more studies to include process evaluations and qualitative evidence.

Find a great summary of it here.

Friday, March 1, 2013

Sequestration Day

Today, the spending cuts across the United States federal government start to take place in the well publicized process of sequestration.  My understanding is that the two political parties in control of the executive and legislative branches agreed that the United States budget needs an overhaul, disagreed on what budget priorities should be, and so agreed that they needed a stick to force them into some sort of agreement.  That stick was sequestration, an across the board spending reductions of approximately $85 billion in 2013. Between 2013 and 2021, sequestration is supposed to reduce national deficit by $1.2 trillion in spending and interest payments.  "Across the board" refers to the concept that spending reductions need to be evenly distributed at the "program, project, and activity level".  The National Park Service can't, for example, close down the Washington Monument while hiring new people in the Everglades.  Or maybe they can, I'm no sequestration expert.  But anyway, apparently the stick to force agreement was not threatening enough for either side.  And so Congress went home yesterday without reaching an agreement.  Side note: I don't understand why Congress doesn't have to work on Friday.  Are they starting sequestration-induced furloughs now?

So why am I writing about sequestration for a blog devoted to global water and sanitation issues?  Because reduced U.S. government spending under the sequestration impacts the research and development projects in the WASH sector.  First, there's cuts in foreign aid.  Approximately 5.3% cost reductions in foreign aid for FY2013, followed by a decade of reductions estimated at $50 billion.  $50 billion is, approximately, what the U.S. spends on total foreign aid every year.  Including diplomacy.  The money goes to $1.5 billion line item to support the USAID (big proponents of WASH funding), $7.9 billion for the Global Health Initiative, $470 million toward building resiliency in the face of Global Climate Change, and $1.3 billion in development in poorest countries.  Reduce those numbers by approximately 5% this year and you have an idea about international impacts of sequestration on foreign aid.

Second, there's cuts to U.S. science funding.  I've heard anecdotally that NIH and NSF, the top two research funding agencies  handle cuts differently.  The NIH attempts to keep the number of research grants consistent at the expense of the funding size of each grant.    I don't know if that's true.  But what I have seen is that the sequester means a reduction in NIH's budget of 5.1%, corresponding to approximately $1.6 billion.  That's huge.  That's over 3000 years of R01 grant funding (at approximately $500k per year).  I just divided those numbers, so that's probably an overestimate (no indirect costs, NIH admin support, etc.).  And also, NIH can't just cut R01 funding (remember the "across the boards" thing from earlier).  But you get the idea.  That's huge.  And NIH is the single largest source of global research and development funds, providing an estimated 62% of total global basic research and development.  That same link suggests the NIH is providing research funds to 90 countries around the world.  So a 5.1% reduction in NIH spending from sequestration will reduce total global health basic R&D by 3.1%.  Did I mention how huge this is?

I've heard (and just found this article that says) that the NSF keeps the size of the grants, and cuts the number of grants.  That article is estimating that NSF will award 1000 fewer grants under sequestration this year.  That's hundreds of projects and careers set back by lack of funding.

So I was hoping to write an in depth analysis about the impacts of sequestration on international WASH research, and instead provided a really rough overview.  But that's mostly because there remains a lot of uncertainty about what sequestration will mean.  In the meantime, if you are an American citizen, write your local representative asking them to get to work coming up with a more targeted approach to fixing the U.S. Budget mess.  They listen.  They might respond with a form letter that clearly misses the point of what you were trying to say.  But they listen.

Tuesday, February 26, 2013

Automatic chlorination on TEDx

Excellent TEDx talk by Indian engineer Suprio Das, inventor of the ZIMBA, an automatic chlorination device for disinfecting drinking water. Stanford and ZIMBA are collaborating to test out the ZIMBA in urban low-income communities in Dhaka. Some devices have been installed for over 1 year - each one has treated over 1 million liters of water. 

Wednesday, January 9, 2013

An in-depth analysis of a piece of shit:

New PLOS research article on distribution of helminth eggs in human stool, important work and a title to envy: