How does fighting diarrhoea stack up to malaria in effectiveness?

by MichaelDello9th Oct 20159 comments

2

Cause candidatesGlobal health and development
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I saw an infographic about diarrhoea the other day that really caught my attention with some big statistics. It got me thinking that I had never really considered combating diarrhoea specifically as an avenue for improving global health. Typically I've focussed on Malaria, specifically through the Against Malaria Foundation (AMF). Below is a comparison between the impacts diarrhoea and malaria and the costs of combating them. The following figures for diarrhoea are taken from this infographic and compared where possible to figures from malaria (sources listed). The infographic didn’t have a logo, producer or sources on it, and after research some of the figures don’t seem to check out.

Diarrhoea is responsible for 1.5 million child deaths under 5 each year. (Note that according to (b) as of 2013 diarrhoea kills around 760,000 children under 5 per year, so this doesn’t seem to check out)

Malaria was responsible for 455,520 child deaths under 5 in 2013. (a) 

Wash programs have the potential to save over 2500 lives per day (175,000 per year). (I’m always sceptical of the use of the word ‘potential’) 

A safe water supply can reduce diarrhoea by 21%.  

About half of the World's Hospital [sic] beds are occupied by patients with a water-related illness such as diarrhoea. (Not a proper source, but (h) repeats this figure)

Diarrhoea kills more children than AIDS, measles and malaria combined.

Diarrhoea killed an estimated 1.26 million people in 2013 (e). In 2013, 1.5 million people died of HIV related illnesses (d), 145,700 people died from measles (c) and 584,000 people died from malaria (a), giving a total of 2.23 million deaths. This statement doesn’t seem to check out, and by this time I’m getting rather suspicious of the infographics’ validity.

In India alone, water-related diseases cost the economy 73 million working days per year. (Figure validated by (f))

I can’t find a recent figure for malaria to compare, but (g) has good related information.

For every $1 invested in water, sanitisation and hygiene, $8 is returned in increased productivity. (I can’t vet this, but (i) has good related information)

433 million school days are lost each year due to water-related diseases. (Not a proper source, but (h) repeats this figure)

WHO estimates that 94% of all occurrences of diarrhoeal diseases are completely preventable.


The latest figures suggest that AMF can save a life that would have been lost otherwise to malaria for ~$3,340 (j) by distributing bed nets to keep mosquitos away from people while they sleep.

In The Life You Can Save, Peter Singer says “WHO, for example, estimates that many of the 3 million people who die annually from diarrhea or its complications can be saved by an extraordinarily simple recipe for oral rehydration therapy: a large pinch of salt and a fistful of sugar dissolved in a jug of clean water. This lifesaving remedy can be assembled for a few cents, if only people know about it. UNICEF estimates that the hundreds of thousands of children who still die of measles each year could be saved by a vaccine costing less than $1 a dose… while these low figures are undoubtedly an important part of the charities' efforts to attract donors, they are, unfortunately, not an accurate measure of the true cost of saving a life.

An article from The Guardian says “Right now Unicef is chlorinating water, making it safe to drink. At a cost of only 17p, it can provide the oral rehydration salts that will save a child from fatal diarrhoea.” (k) But there is a gap between providing the rehydration salts and directly saving one life. The child consuming the salts may not have died anyway, or they might not use it.

In Disease Control Priorities In Developing Countries (m; 2nd edition released 2006), it is stated that the cost of saving a life from diarrheal diseases is much more cost effective through educational intervention (~ US$500 “and could be as low as US$14”). “Scenarios with a high cost per life saved (more than US$6,000) are when prevalence rates are low or when implementation costs for quality-related interventions are high.”

This would suggest that educational interventions targeting diarrheal diseases is more cost effective at saving lives than distributing bed nets. However, this is an older figure (pre-2006) and isn’t backed up with the name of an organisation that can achieve this. It certainly highlights that diarrhoea may be worthy of more focus for reducing deaths due to widespread diseases than malaria. The last quotes also seem to suggest that perhaps an educational approach to combating malaria may be more effective than traditional approaches. This is rather typical of similar issues in developing countries.

I haven’t been able to find much research on water charities on the GiveWell website. A stub page exists, with the conclusion “In 2011, we identified 43 water charities and visited their websites to determine whether they published information online to answer the above question. By and large, we found limited information that answered our questions. We ultimately contacted six organizations and our reviews of 4 of them are still pending.” It would seem that a renewed focus on water charities should be undertaken.

The verdict

Some of the statements listed in the infographic don’t appear to be entirely accurate, though the scale of the problem of diarrhoea is comparable to that of malaria. Initial findings reported here suggest that treating diarrhoea may be as or even more cost effective than combating diarrhoea. It is recommended that more research into the effectiveness of water charities be undertaken given the potential for high effectiveness, especially through educational programs regarding diarrhoea and related diseases.

Note: Many figures listed have an uncertainty range. A mean value is generally taken for simplicity.


References


(a) http://www.who.int/malaria/areas/high_risk_groups/children/en/

(b) http://www.who.int/mediacentre/factsheets/fs330/en/

(c) www.who.int/mediacentre/factsheets/fs286/en/

(d) www.who.int/gho/hiv/epidemic_status/deaths/en/

(e) https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4340604/

(f) www.wateraid.org/~/media/.../drinking-water-quality-rural-india.pdf

(g) http://www.ncbi.nlm.nih.gov/books/NBK1720/

(h) http://thewaterproject.org/health

(i) http://www.who.int/water_sanitation_health/wsh0404summary/en/

(j) http://www.givewell.org/international/top-charities/AMF

(k) http://www.theguardian.com/world/2000/mar/05/mozambique.theobserver

(l) http://www.effective-altruism.com/ea/5e/efficient_charity_do_unto_others/

(m) https://books.google.com.au/books?isbn=0821361805

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Givewell published their findings on water treatment interventions in 2013 did you miss this page? I think it is very plausible that such interventions could be a highly effective cause area With more research though.

Interesting, I suppose I must have... Thanks for the link.

It seems that a lack of good evidence is rather crippling here. I wonder how much it would cost to set up a trial with a good chance of determining the effectiveness of water treatment and related interventions. It almost seems like a cop out to leave things at that point. Surely, if there's a chance that water treatments are more effective at saving lives than malaria interventions and the costs of setting up a good trial are not exorbitant, it would be worth funding such a study.

Yes potentially. I know that Evidence Action (the charity that runs Deworm the World) also has a water dispensing charity http://www.evidenceaction.org/dispensers/ .

GWWC has a good blog post from 2014 about them and the potential for research in this area. https://www.givingwhatwecan.org/blog/2014-01-28/dispensers-for-safe-water

As a general point, I think there are a whole host of potentially high impact charities (such as those that are "other outstanding charities") that have not received much attention in the EA community, and could be good targets for more research and highlighting in a similar way.

Hi Michael,

great post! We're currently looking into this more.

Diarrheal disease really is responsible for a lot of ill health. Here's a breakdown of the reasons for diarrhea taken from (http://ihmeuw.org/3oxy) with some observations on each of those risk factors in terms of highly effective interventions:

The associated risk are:

1.‘Behavioural’ risk factors:

1.1 Malnutrition

1.1.1 Childhood undernutrition

  • Solutions: agricultural aid tries to work on this
  • Givedirectly, because people buy more food
  • deworming, because worms might have a little effect on weight (the effect might be small, but cost-effectiveness might still be high)

1.1.2 suboptimal breastfeeding

  • there DMI is a good candidate, because they encourage breastfeeding, but the midline results were not significant.

1.1.3 Vitamin A and Zinc deficiency

  • this is partly because we recommend Project Healthy Children
  • Living Goods also sells vitamins

  • 'environmental' risk factors

2.1 'WASH' interventions:

2.1.1 Unsafe Water

Potential interventions:

2.1.2 unsafe sanitation

potential interventions:

  • DMI tries to promote latrine ownership - no sig. results so far.
  • I recently saw the folks from peepoople.com speak at a conference and this might be an innovative, high cost-effectiveness approach - but there is not enough evidence out yet. Generally, my sense is that toilets are very difficult.
  • Handwashing (can be done with ash, doesn't even have to be soap). DMI promotes handwashing, but the results for this are still out.

  • Treament:

  • Living Goods also sells an oral rehydration therapy product

  • DMI, in the midline results of their trial, found that they significantly increased the number of people who sought help at a clinic for diarrhea.
  1. New interesting research in this area:

  2. very good recent cluster RCT on:

The Effect of Improved Water Supply on Diarrhea Prevalence of Children under Five in the Volta Region of Ghana: A Cluster-Randomized Controlled Trial.

Supplying clean water by drilling or rehabilitating boreholes reduced diarrheal prevalence by 11% in this study. The study convincingly gets around some methodological issues with self-reported diarrhea. http://www.ncbi.nlm.nih.gov/pubmed/26404337

  • Effects of better WASH beyond health:

Effect of Early Life Exposure to a Clean Water Intervention on Health and Socioeconomic Status in Adulthood: Evidence from a Quasi-Experimental Cohort Study in Mexico*

“Early childhood diarrhea jeopardizes child development by diverting nutrition away from physical and mental growth towards fighting illness. Consequently, early exposure to clean water interventions, which reduce diarrhea risk, may confer positive effects on adult health and well-being that are typically not accounted for in resource allocation decisions. We found that early life exposure to a clean water intervention in Mexico in 1991 led to increases in adult height for men and completed schooling for women.” http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.363.1560&rep=rep1&type=pdf

I hope this helps.

I looked into this about 14 years ago and heard that there was limited room for more funding for some of the most promising interventions. For example, this applied to the "oral rehydration salts" that you mentioned, and which Peter Unger's very EA book Living High and Letting Die - which I read at the time - advocated donating and earning lots of money for. (Obligatory plug: if you want to buy it, you can do so via Amazon Shop for Charity search). Does anyone know what the current RFMF picture?

"Malaria was responsible for 455,520 million child deaths under 5 in 2013. (a) "

Wait... yeah, it's actually 455,520 child deaths. I panicked for a second, there.

Thanks for spotting that, yes that would be a lot.