Can and should sanitation and hygiene programmes be expected to achieve health impacts?

Richard C. Carter

doi:10.3362/1756-3488.2017.005

Can and should sanitation and hygiene programmes be expected to achieve health impacts?

Although the anticipated health benefits are not the only reason for undertaking sanitation and hygiene programmes, they do represent an important part of the justification. Studies and reviews over recent years have shown, however, that the health impacts of sanitation programmes can be quite small or even negligible. They have also provided no solid evidence that integrated (water, sanitation, hygiene) programming has any greater effect than addressing one or two of these components alone. Two questions arise: first, whether a certain level of sanitation usage and hygiene practice within a community is needed in order to achieve a measurable health impact (i.e. whether a minimum percentage of the population should be using safe sanitation); second, whether sanitation and hygiene interventions undertaken without accompanying water supply improvements are likely to have significant health benefits. In this opinion paper some plausible and practically relevant answers to these questions are extracted from the relevant literature. The conclusions are that a high level of sanitation usage (well over 65 per cent) and widespread handwashing practice are necessary to achieve significant health impact; and that in situations where water services are poor, sanitation and hygiene interventions, while valuable for other reasons, are unlikely to have significant health impacts. Sanitation and hygiene programmes may be justifiable even if they do not immediately achieve high levels of compliance and corresponding water supply improvements are not made; however, the justification should not be presented on the grounds of short-term health benefits.

Andrés, L.A., Briceño, B., Chase, C. and Echenique, J.A. (2014) Sanitation and Externalities: Evidence from Early Childhood Health in Rural India [online], Policy Research Working Paper No. 6737, Washington, DC: World Bank <http://dx.doi.org/10.1596/1813-9450-6737> [accessed 23 November 2016].

Brown, J. and Clasen, T. (2012) ‘High adherence is necessary to realize health gains from water quality interventions’, PLoS ONE 7(5): e36735 <http://dx.doi.org/10.1371/journal.pone.0036735>.

Brown, J., Cairncross, S. and Ensink, J.H.J. (2013) ‘Water, sanitation, hygiene and enteric infections in children’, Archives of Disease in Childhood 98: 629–34 <http://dx.doi.org/10.1136/archdischild-2011-301528>.

Cairncross, S. and Valdmanis, V. (2004) Water Supply, Sanitation, and Hygiene Promotion [online], Disease Control Priorities Project Working Paper No. 28, July 2004 <https://www.ncbi.nlm.nih.gov/books/NBK11755/> [accessed 14 November 2016].

Cairncross, S., Blumenthal, U., Kolsky, P., Moraes, P.L. and Tayeh, A. (1996) ‘The public and domestic domains in the transmission of disease’, Tropical Medicine and International Health 1(1): 27–34 <http://dx.doi.org/10.1046/j.1365-3156.1996.d01-9.x>.

Cairncross, S., O’Neill, D., McCoy, A. and Sethi, D. (2003) Health, Environment and the Burden of Disease: A Guidance Note [pdf], London: DFID <www.lboro.ac.uk/well/resources/Publications/DFID%20Health.pdf> [accessed 14 November 2016].

Carter, R.C. (2013) ‘Editorial: researching “how” rather than “why”’, Waterlines 32(1): 3–4 <http://dx.doi.org/10.3362/1756-3488.2013.001>.

Clasen, T., Boisson, S., Routray, P., Torondel, B., Bell, M., Cumming, O., Ensink, J., Freeman, M., Jenkins, M., Odagiri, M., Ray, S., Sinha, A., Suar, M. and Schmidt, W.P. (2014) ‘Effectiveness of a rural sanitation programme on diarrhoea, soil-transmitted helminth infection, and child malnutrition in Odisha, India: a cluster-randomised trial’, The Lancet Global Health 2(11): e645–53 <http://dx.doi.org/10.1016/S2214-109X(14)70307-9>.

Coffey, D., Gupta, A., Hathi, P., Spears, D., Srivastav, N. and Vyas, S. (2015) Culture and the Health Transition: Understanding Sanitation Behaviour in Rural North India [pdf], IGC Working Paper April 2015 <www.theigc.org/wp-content/uploads/2015/04/Coffey-et-al-2015-Working-Paper.pdf> [accessed 14 November 2016].

DFID (2013) Water, Sanitation and Hygiene: Evidence Paper, May 2013 [pdf], London: DFID <https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/193656/WASH-evidence-paper-april2013.pdf> [accessed 25 November 2016].

Duflo, E., Greenstone, M., Guiteras, R. and Clasen, T. (2015) Toilets Can Work: Short and Medium Run Health Impacts of Addressing Complementarities and Externalities in Water and Sanitation [online], NBER Working Paper w21521, 2015 <http://economics.mit.edu/files/10743> [accessed 14 November 2016].

Esrey, S.A., Potash, J.B., Roberts, L. and Shiff, C. (1991) ‘Effects of improved water supply and sanitation on ascariasis, diarrhea, dracunculiasis, hookworm infection, schistosomiasis and trachoma’, Bulletin of the World Health Organisation 69(5): 609–21.

Fewtrell et al. (2005) ‘Water, sanitation, and hygiene interventions to reduce diarrhoea in less developed countries: a systematic review and meta-analysis’, The Lancet Infectious Diseases, 5(1): 42–52 <http://dx.doi.org/10.1016/S1473-3099(04)01253-8>.

Fuller, J.A. and Eisenberg, J.N.S. (2016) ‘Herd protection from drinking water, sanitation and hygiene interventions’, American Society of Tropical Medicine and Hygiene 95(5): 1201–10 <http://dx.doi.org/10.4269/ajtmh.15-0677>.

Fuller, J.A., Westphal, J.A., Kenney, B. and Eisenberg, J.N.S. (2015) ‘The joint effects of water and sanitation on diarrhoeal disease: a multi-country analysis of the Demographic and Health Surveys’, Tropical Medicine and International Health 20(3): 284–92 <http://dx.doi.org/10.1111/tmi.12441>.

Fuller, J.A., Villamor, E., Cevallos, W., Trostle, J. and Eisenberg, J.N.S. (2016) ‘I get height with a little help from my friends: herd protection from sanitation on child growth in rural Ecuador’, International Journal of Epidemiology 2016: 45(2): 1–10 <http://dx.doi.org/10.1093/ije/dyv368>.

Gertler, P., Shah, M., Alzua, M.L., Cameron, L., Martinez, S. and Patil, S. (2015) How Does Health Promotion Work? Evidence From The Dirty Business of Eliminating Open Defecation [pdf], NBER Working Paper no. 20997, Cambridge Mass: NBER <http://users.monash.edu.au/~clisa/papers/NBER_w20997.pdf> [accessed 14 November 2016].

Green, D. (2016) ‘Book review: the power of positive deviance’ [blog], Oxfam <http://oxfamblogs.org/fp2p/book-review-the-power-of-positive-deviance/> [accessed 25 November 2016].

Hunter, P.R. and Prüss-Ustün, A. (2016) Have we substantially underestimated the impact of improved sanitation coverage on child health? A generalized additive model panel analysis of global data on child mortality and malnutrition’, PLoS ONE 11(10): e0164571 <http://dx.doi.org/10.1371/journal.pone.0164571>.

Hunter, P.R., Pond, K. and Jagals, P. (2009) ‘An assessment of the costs and benefits of interventions aimed at improving rural community water supplies in developed countries’, Science of the Total Environment 407: 3681–5 <http://dx.doi.org/10.1016/j.scitotenv.2009.03.013>.

Indrayan, A. (nd) Varieties of Bias to Guard Against [pdf] <www.medicalbiostatistics.com/Types%20of%20bias.pdf> [accessed 14 November 2016].

Moreland, J.P. and Craig, W.L. (2003) Philosophical Foundations for a Christian Worldview, Downers Grove, IL: InterVarsity Press, pp. 155–6.

Patil, S.R., Arnold, B.F., Salvatore, A.L., Briceno, B., Ganguly, S., Colford, J.M. Jr and Gertler, P.J. (2014) ‘The effect of India’s total sanitation campaign on defecation behaviors and child health in rural Madhya Pradesh: a cluster randomized controlled trial’, PLOS Medicine 11(8): e1001709 <http://dx.doi.org/10.1371/journal.pmed.1001709>.

Pickering, A.J., Djebbari, H., Lopez, C., Coulibaly, M. and Alzua, M.L. (2015) ‘Effect of a community-led sanitation intervention on child diarrhoea and child growth in rural Mali: a cluster-randomised controlled trial’, Lancet Global Health 3: e701–11 <http://dx.doi.org/10.1016/S2214-109X(15)00144-8>.

Prüss-Ustün, A., Bos, R., Gore, F. and Bartram, J. (2008) Safer Water, Better Health: Costs, Benefits and Sustainability of Interventions to Protect and Promote Health [pdf], Geneva: World Health Organization <http://apps.who.int/iris/bitstream/10665/43840/1/9789241596435_eng.pdf> [accessed 14 November 2016].

Schmidt, W-P. (2014) ‘The elusive effect of water and sanitation on the global burden of disease: Editorial’, Tropical Medicine and International Health 19(5): 522–7 <http://dx.doi.org/10.1111/tmi.12286>.

Schmidt, W-P. (2015) ‘Seven trials, seven question marks: Comment’, The Lancet Global Health 3: e659–60 <http://dx.doi.org/10.1016/S2214-109X(15)00182-5>.

Schmidt, W-P. and Cairncross, S. (2009) ‘Household water treatment in poor populations: is there enough evidence for scaling up now?’ Environmental Science & Technology 43(4): 986–92 <http://dx.doi.org/10.1021/es802232w>.

Sclar, G.D., Penakalapati, G., Amato, H.K., Garn, J.V., Alexander, K., Freeman, M.C., Boisson, S., Medlicott, K.O. and Clasen, T. (2016) ‘Assessing the impact of sanitation on indicators of fecal exposure along principal transmission pathways: a systematic review’, International Journal of Hygiene and Environmental Health 219(8): 709–23 <http://dx.doi.org/10.1016/j.ijheh.2016.09.021>.

Scott, B. (2006) Health Impacts of Improved Household Sanitation [online], WELL Factsheet November 2006 <www.lboro.ac.uk/well/resources/fact-sheets/fact-sheets-htm/Household%20Sanitation.htm> [accessed 14 November 2016].

Vyas, S., Spears, D., Kov, P. and Smets, S. (2013) Investing in the Next Generation: Growing Tall and Smart with Toilets – Stopping Open Defecation Improves Children’s Height in Cambodia [pdf], Washington, DC: Water and Sanitation Program, World Bank <https://www.wsp.org/sites/wsp.org/files/publications/Growing-Tall-and-Smart-with-Toilets-Research-Brief.pdf> [accessed 14 November 2016].

Wagner, E.G. and Lanoix, J.N. (1958) Excreta Disposal for Rural Areas and Small Communities, Geneva: World Health Organization <http://apps.who.int/iris/bitstream/10665/41687/1/WHO_MONO_39_(part1).pdf> [accessed 14 November 2016].