Archive for the 'Academic Paper Review' Category

myopia

The terms myopia and myopic (or the common terms short sightedness or short sighted) have also been used metaphorically to refer to cognitive thinking and decision making that is narrow sighted or lacking in concern for wider interests or longer-term consequences.” -Wikipedia (8/9/09)

I started to think about this term after reading a paper from Environmental Health Perspectives called Public Health Strategies for Western Bangladesh That Address Arsenic, Manganese, Uranium, and Other Toxic Elements in Drinking Water. The authors of this paper sampled a number of tube wells in Western Bangladesh to investigate the water quality, not only with respect to Arsenic but an array of other potential toxicants.   They found levels exceeding WHO health-based drinking water guidelines for Uranium, Manganese, Arsenic, Chromium, and Lead along with significant levels of other important elements like Antimony.  Why is this interesting one may ask?

After drilling millions of tube wells to save people from the morbidity and mortality related to gastrointestinal illnesses, UN agencies and the Bangladesh Government realized that they had exposed millions of people to arsenic.  This arsenic shifted the causes of illness and death related to water to other ailments like cancer (lung/bladder/skin).  Most of you know how this happened but in case you don’t…They simply didn’t test the water for Arsenic!!!

With so much focus on dealing with the arsenic problem, are we forgetting about other potential toxicants in the water?  This study seems to suggest we may be – at least in some parts of Bangladesh.  The government of Bangledesh is focused on testing each and every well for As but does not look at many of these other elements mentioned in the article (it should be noted that Arsenic probably poses the biggest threat to the population but the possible effects of the others are by no means negligible).   The authors note that in wells exceeding limits for As Uranium was not often found in quantities above the limit. However, the household treatment technology that many use to remove arsenic could actually increase the dissolved Uranium concentration (by making otherwise insoluble form soluble)….

This type of myopia happens all the time the water and sanitation sector.  We want to focus only on provision of clean water but don’t want to think about the multiple other pathways for enteric pathogen transmission.   We focus on toilets but forget that there is no readily accessible water to wash hands….Hopefully it won’t take another mass poisoning for us to wake up and look at the big picture.

Check out the article it is pretty interesting (oh and try to estimate the carbon footprint of the samples that made their way from India to Dubai to France to Vermont,USA)

Scaling Household Water Treatment

Tom Clasen from LSHTM recently prepared a paper for the WHO entitled “Scaling Up Household Water Treatment Among Low-Income Populations”.  In this paper he reviews research and interventions (scale and effectiveness) related to Household Water Treatment (HWT).  Boiling, Chlorine Disinfection (NaClO and NaDCC), SODIS, and filters are the main technology focuses of this insightful document.

Clasen comes up with some interesting stats on global use of HWT technologies.

HWT Method 2007 Use/Scale
NaClO (SWS)* 7.6 billion litres [60% of sales in 3 countries!!]
NaDCC* 2.86 billion litres [majority of sales in Kenya]
Ceramic Filters 2.6 billion litres
Biosand Filters 1.3 billion litres
SODIS 2.1 million users (estimate litres as you wish..5 l/p/d? 10? 20? 40?)

*does not include emergency use, (2007 statistics)

Although these numbers seem huge (well, they are quite impressive), it is important to keep them in perspective. More than 350 million people rely on boiling (not including much of China and other Asian communities who boil) and the UN Joint Monitoring Program estimates that nearly 900 million people still rely on unimproved sources of drinking water.  How are we going to bridge this HUGE gap?

We have all heard the buzz phrase  “SCALING UP, ” and many have asked ourselves what that means with respect to water and sanitation interventions.  No it is not just a word UN and development agencies toss around for kicks (well may be it is…I once heard people talking about scaling up scale up activities!).  Fortunately, Clasen talks a lot about what it means to scale up water interventions and suggests that “coverage” is an important metric but not the ultimate one.  It may be necessary but NOT sufficient for true health benefits of household treatment to impact the target populations.  What we are concerned with in “Scaling Up” is not only coverage but uptake.   Uptake is really the challenge for all of us and we don’t like to measure it too often (it is much harder than figuring out presumed coverage)…We can come up with great technologies but can we make them affordable, desirable, and usable?  Think about all of the great ideas out there like the Lifestraw and Lifefilter (and other technologies reviewed in the Clasen Paper)….what is going wrong?

In light of the current situation Clasen highlights some key constraints the must be overcome to scale up any HWT intervention:

…These [constaints] include 1) the persistent belief that diarrhoea is not a disease; 2) scepticism about the effectiveness of water quality interventions; 3) special challenges associated with uptake, including low aesthetic appeal for consumables, high up-front cost, the need to replace components for durables and the need to continuously use the product, even in the face of disease through other transmission pathways; 4) public health suspicion of the agenda of commercial products and strategies; 5) the orphan status of HWTS at the public sector level, with neither the water sector nor the health sector willing and able to assume ownership of the intervention; 6) minimal public sector participation in the promotion of HWTS; 7) a lack of focused international effort and commitment to advance HWTS; and 8)perceived policy conflict with efforts to promote piped-in water supplies.

In learning how to overcome some of these issues the paper looks at other interventions that have been successfully implemented at a large scale including Oral Rehydration Salts, Treated Bednets, and Guinea Worm Filters.  How did people start to accept these technologies, recognize their inherent value, and begin to use them correctly? Can these experiences translate to the challenge of providing clean water?  There are a lot of differences but Clasen suggests we can learn from their failures and successes.

Clasen goes on to argue that we will not meet the needs of the global poor with current technologies combined with current intervention strategies.

The gap between where we are and where we need to be is too great, given the urgency of the need. What is needed is a breakthrough. The largely public health orientation that has brought HWTS to its present point now needs to enlist the help of other experts: consumer researchers, product designers, educators, social entrepreneurs, micro-financiers, business strategists and policy advocates. The private sector is one obvious partner; it possesses not only much of this expertise but also the incentive and resources to develop the products, campaigns and delivery models for creating and meeting demand on a large scale. At the same time, market-driven, cost-recovery models are not likely to reach vast populations at the bottom of the economic pyramid where the disease burden associated with unsafe drinking-water is heaviest. As WHO ultimately concluded in the case of insecticide-treated mosquito nets, mass coverage among the most vulnerable populations may be impossible without free or heavily subsidized distribution. For this population segment, the public sector, UN organizations and NGOs that have special access to these population segments must engage donors to provide the necessary funding and then demonstrate their capacity to achieve both scale and uptake. Governments and international organizations can also help encourage responsible action by the private sector by implementing performance and safety standards and certification for HWTS products; reducing barriers to importation, production and distribution of proven products; and providing incentives for reaching marginalized populations.

He finishes with a number of suggestions on how we can accelerate the scale up of HWT approaches.

1. Focus on the users.
2. Develop and use partners.
3. Improve and expand on boiling.
4. Continue to pursue non-commercial strategies.
5. Continue to pursue market-driven strategies.
6. Leverage existing local strengths.
7. Initiate and use relevant, practical research.
8. Overcome public policy barriers to advancing HWTS. The Joint Monitoring Programme for Water Supply and Sanitation (JMP) of WHO and the United Nations Children’s Fund should clarify the contribution that safe and effective HWTS can make towards advancing health, even though, for policy and methodological reasons, it should not count towards the MDG water target. National governments should embrace the intervention while they work to extend piped-in supplies of treated water.
9. Engage national and regional governments.
10. Engage international leadership to support HWTS.

Hopefully some of this paper will be read by enough people in positions of power to change course….There are so many opportunities and many examples in other sectors to learn from.

New SODIS Trials

Thanks to USAID’s Sanitation/Water/Env Health News Service service I get emails with a list of new abstracts every few days.  Results from a new Solar Disinfection (SODIS) randomized controlled study came to my inbox today.  This study, a collaborative effort between researchers in Bolivia, Switzerland, and the US (UC Berkley), sought to investigate the health impacts from a SODIS intervention through a cluster-randomized controlled study.

PLoS Medicine – August 2009 | Volume 6 | Issue 8 | e1000125

Solar Drinking Water Disinfection (SODIS) to Reduce Childhood Diarrhoea in Rural Bolivia: A Cluster-Randomized, Controlled Trial, Daniel Mausezah, Andri Christen, Gonzalo Duran Pacheco, Fidel Alvarez Tellez, Mercedes Iriarte Maria E. Zapata, Myriam Cevallos, Jan Hattendorf, Monica Daigl Cattaneo, Benjamin Arnold, Thomas A. Smith, John M. Colford Jr

Theoretically, SODIS can really have profound impacts on biological contaminants but no few large-scale rigorous studies have shown that it actually works in the field.  Some of the common challenges include behavior change and proper use of the technology.   It takes much more than a good technology to impact diarrhea prevalence and this study aimed to find out what could be achieved.

In the end the researchers found no statistically significant impact on diarrhea prevalence from the SODIS user group.  Although this sounds depressing, there are some lessons that can be learned from this and applied to a subsequent attempt.

1.  Study Design – Zulfiqar Bhutta, from the Aga Khan University, suggested in a follow up “Perspective” article that the study was designed to detect larger changes in diarrhea prevalence and the researchers may have been better off with a stepped wedge design.  I am not sure what the best design would be (as I have not looked into this in depth) but if they expected lower prevalence reduction rates (which could still be important) I’ll bet the study design would have differed.

2. Focus on Behavior Change -Despite the intense software components to this study (conducted by an NGO Project Concern International) only ~30% of the SODIS group complied with the SODIS method.  It would be interesting to learn more about why people failed to use the SODIS method and whether changes can be made to the education/software aspects of the project to improve uptake.

The full text of this article can be found here.



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