Presentation. The Author(s), all rights reserved

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1 Presentation Presentation from the 2008World Water Week in Stockholm The Author(s), all rights reserved

2 Household Water Treatment: effectiveness, cost-effectiveness and the challenges and policy issues of scaling up Thomas Clasen JD PhD Thomas Clasen, JD, PhD Disease Control & Vector Biology Unit Department Infectious & Tropical Diseases London School of Hygiene & Tropical Medicine

3 Leading Causes of Deaths from Infectious Diseases 2004 World Health Report Deaths (000s) Respiratory Infections ns HIV/AID DS Diarrhoe oeal Disease ses Tuberculosi sis Malari ria Measle les

4 Childhood Mortality by Cause Black RE, Morris SS & Bryce J (2003). Where and why are 10 million children dying every year? Lancet 361:

5 Environmental Barriers to Faecal-Oral Transmission Primary Barrier Sanitation (proper excreta disposal) Hygiene (hand washing) Secondary Barriers Water quality (treatment & safe storage) Water quantity (personal and domestic hygiene) Hygiene (especially hand washing) Proper cooking/food handing practices

6 Reduction in Diarrhoea from Improvements in Water Quality Expected reduction in diarrhoeal disease morbidity from improvements in one or more components of water and sanitation (Esrey, 1991) All Studies No. Studies Reduction Rigorous Studies No. Studies Reduction Water and Sanitation 7 20% 2 30% Snittin Sanitation 11 22% 5 36% Water Quality and Quantity 22 16% 2 17% Water Quality 7 17% 4 15% Water Quantity 7 27% 5 20% Hygiene 6 33% 6 33%

7 Systematic Review Wright et al.* Systematic review and meta-analysis of 57 studies measuring bacteria counts for source water and stored water in the home. Results: The bacteriological quality of drinking water significantly declined after collection in many settings. Conclusion: Policies that aim to improve water quality through source improvements may be compromised by post-collection contamination. Safer household water storage and treatment is recommended to prevent this, together with point-of-use water quality monitoring. *WrightJ,GundryS,ConroyR(2004).Household di drinking water in developing countries: ti a systematic ti review of microbiological contamination between source and point-of-use. Tropical Med. Int l Health 9(1):

8 Interventions at Source

9 Safe -Microbiological Quality Results of eight-country (Bangladesh, China, Jordon, Tajikistand, India, Nicaragua, Nigeria, Ethiopia) Rapid Assessment of Drinking Water Quality (RADWQ) Water supply technology Mean portion of samples complying with WHO guideline value for TTC Protected dug well 43% (range 19% to 56%) Protected springs 63% (Ethiopia 43%, Tajikistan 82%) Boreholes 69% (range 39%-99%) Utility piped water supplies 89% (range 39%-99%) JMP RADWQ (in press)

10 Interventions at the Household

11 What about boiling? Sub-optimal microbiological performance, probably due to recontamination at o after boiling (Gupta 2006; Handzel 2007; Oswald 2007; Clasen 2008; Clasen 2008a). Potentially high cost: US$7.99 to US$8.34 per household per year in India (McLaughlin 2006); US$3.24 to $20.16, in Vietnam) (do Hoang 2007) Indoor air pollution from cooking with biomass associated with reduced birth weight, respiratory infections, anemia, stunting g( (Retherford 2006) Boiling water at home is also associated with higher levels of burn accidents. In Sao Paulo, Brazil, boiling water was responsible for 59% of burn accidents among children under 3 years (Rossi 1998). Other issues: Suitability, environmental sustainability

12 Cochrane Review Clasen T, Roberts I, Rabie T, Schmidt WCi W, Cairncross SI S. Interventions to improve water quality for preventing diarrhoea (A Cochrane Review). In: The Cochrane Library, Issue 3, 2006.

13 Effectiveness: Intervention Type (all age)

14 Summary of Effectiveness All ages Intervention Type (no. trials) Estimate (random) % Δ (1-RR) 95% CI of Estimate Heterogeneity* (Chi-square) Source (6) % 0.53 to 1.01 p< Household (32) % 0.39 to 0.73 p< Filtration (6) % 0.28 to 0.49 p=0.56 Chlorination (16) % 0.52 to 0.75 p< Solar Disinfection (2) % 0.63 to 0.74 p=0.73 Flocc/Disinfection (7) % 0.20 to 1.16 p< Flocc/Disinfection (ex % 0.58 to 0.82 p=0.08 Doocy) Impr. Storage (1) % 0.61 to 1.03 n.a. *N h i f h i l l ( <0 10) l d l i *Note that in a test for heterogeneity, a low p-value (eg <0.10) suggests an actual underlying difference in effect between studies that is unlikely to be attributable to chance.

15 Summary of Effectiveness Under 5s Intervention Type Estimate % Δ 95% CI of Heterogeneity (no. trials) (random) (1-RR) Estimate (Chi-square) Source (4) % 0.71 to 1.02 p=.007 Household (25) % 0.39 to 0.81 p< Filtration (5) % 0.24 to 0.53 p=0.37 Chlorination (12) % 0.67 to 0.86 p= Solar Disinfection (0) na na na na Flocc/Disinfection (7) % 0.20 to 1.37 p< Flocc/Disinfection (6) (ex Doocy) % 0.61 to 0.84 p=0.10 Impr. Storage (1) % 0.47 to 0.81 n.a.

16 Effectiveness under various conditions i Compliance (use of the intervention) Sanitation (WHO/UNICEF definitions) Water Supply (WHO/UNICEF definitions) Water Quantity (Sphere Project minimums) >50% Compliance (n=16*) 0.46 (0.32 to 0.83) P< Improved (n=11) 048(038to062) 0.48 ( ) P=0.02 Improved (n=11) 0.57 (0.46 to 0.72) P= L/person/day(n=7) 0.56 (0.44 to 0.71) P=0.005 <50% Compliance (n=5) 0.75 (0.63 to 0.90) P=0.06 Unimproved (n=8*) 067(055to081) 0.67 ( ) P< Unimproved (n=24*) 0.66 (0.55 to 0.72) P< <15L/person/day (n=3*) 0.88 (0.72 to ) P=0.01 *Excludes Doocy, 2006

17 Qualifications While two single blinded trials showed effectiveness (pooled estimate, 0.69; 95%CI: ), four double blinded trials showed no statistically significant protective effect (0.92; 95%CI: ). WE NEED MORE BLINDED TRIALS TO RULE IDENTIFY EXTENT OF REPORTING BIAS. Studies of source-based interventions were substantially longer (median 36 months, range 12 to 60 months) than studies of household interventions (5 months, 9.5 weeks to 12 months). WE NEED LONGER TRIALS OF HOUSEHOLD INTERVENTIONS. Trials of household interventions were more likely to be research-driven and may have greater susceptibility to Hawthorne effect, site selection and other biases that may overstate their effectiveness when compared with actual programs. WE NEED TO STUDY AND REPORT ON ACTUAL INTEVENTION PROGRAMS OVER THE LONG TERM.

18 Cost-Effectiveness A comparison of various interventions on a sector-wide basis. Unlike cost-benefit analysis (where all benefits improved productivity, it increased school time, etc. are included in the calculus), CEA is concerned with the realization of a social objective, such as the prevention of disease The output of a CEA is a ratio (the cost-effectiveness ratio) between the cost of the intervention the disability adjusted life years (DALYs) averted as a result of the intervention. Clasen T, Haller L, Walker D, Bartram J, Cairncross S (2007). Cost-effectiveness analysis of water quality interventions for preventing diarrhoeal disease in developing countries. J. Water & Health 5(4):

19 Hardware Costs Product Unit Cost Volume of Cost per First Year Three Year Water Treated 10,000L of Water Treated Cost 1 Cost 1 Gravity filter with two $ ,000L $7.50 $15.00 $30.00 ceramic Stefani candles 3 Locally-fabricated pot-style $ ,000L 000L $7.50 $9.30 $12.90 ceramic water purifiers (CWP) 4 Sodis Solar Disinfection 5 $ L $5.48 $0.80 $2.40 Procter & Gamble PUR $ L $ $91.25 $ Sachet 6 WaterGuard (PSI brand of $0.45 1,000 $4.50 $4.10 $12.32 sodium hypochlorite 7 1. Based on 25L/day/household, or 9,125L/year ml bottle of 1.25% sodium hypochlorite designed to treat 1000L sold at retail in Tanzania and assuming full cost recovery (not subsidized); production cost is $0.17 per bottle (Clasen, 2006a). 3$3.75 per candle, plus $7.50 for vessels and valves. 5,000L capacity per candle according to manufacturer. Replace candles each year. Replace vessels and valve after 3 years. (Clasen 2004) 4. $7.50 initial cost, 25L daily capacity, 2% breakage per month (Brown 2007) 5. $0.10 per bottle (mean price based data from 6 countries) x recommended 4 bottles per household, used for 6 months; capacity based on 2 x 2L bottles (alternate 2 bottles in sun, 2 bottles in household each day) (M. Wegelin personal communication). 6. Manufacturer s suggested retail price of $0.10 per sachet. Assumes no further expenditure for mixing and storing vessels. 7. PSI retail target price in Tanzania for strip pack of 10 x 20L tablets.

20 Summary of Cost Estimates Annual cost per person in US$ of source and household interventions (error bars represent range of costs from programmes) $6.00 $5.00 $4.95 $4.00 $3.60 Cost $3.00 $2.61 $3.03 $2.00 $1.88 $1.00 $0.66 $0.63 $- Source-Africa Source-Asia Source-LA&C Chlorination Ceramic Filtration Solar Disinfection Flocculation- Disinfection System

21 Health Cost Offsets* Costs Averted Variable Data Source Data value (and range) Health sector Unit cost per treatment WHO regional $4.30-$9.70 per visit expenses averted unit cost data $16.10-$39.70 per day due to prevention of diarrhoeal Number of cases WHO BoD data Variable by region disease Visits or days per case Expert opinion 1 outpatient visit per case ( ); 5 days for hospitalized cases Probably much less than 0.5. Hospitalisation rate WHO Data 91.8% ambulatory Patient (householder) costs averted due to prevention of diarrhoeal disease Transport cost per visit Assumptions $0.50 per visit % patients using Assumptions 50% of patients transport Number of cases WHO BoD data Variable by region Visits or days per case Expert opinion 1 outpatient visit per case ( ); 5 days for hospitalized cases Hospitalization rate WHO data 91.8% ambulatory *Adapted from Hutton & Haller (2004). Evaluation of the Costs and Benefits of Water and Sanitation Improvements at the Global Level. Geneva: World Health Organization

22 Gross and Net Costs (50% Coverage) Epidemiological Sub- Region (and countries) Afr-E (Botswana, Burundi, Central African Republic, Congo, Cote d Ivoire, Democratic Republic of the Congo, Eritrea, Ethiopia, Kenya, Lesotho, Malawi, Mozambique, Namibia, Rwanda, South Africa, Swaziland, Uganda, United dr Republic of Tanzania, Zambia, Zimbabwe) Intervention Gross Annual Cost (and range*) in US$ millions Annual Health Cost Offsets in US$ millions Net Annual Cost in US$ millions Source ( ) Household chlorination ( ) Household filtration Household solar disinfection Household flocculation disinfection ( ) ( ) 139.5) ( ) 785.0) *Based on range of cost estimates per person per year for each intervention

23 Cost-effectiveness ratios* Sub- Region Intervention Cost per DALY averted (and range**) in US$s Cost effectiveness (CMH Benchmark) Afr-E Source 123 (14-322) Highly cost effective Household chlorination 53 (41-447) Highly cost effective Household filtration 142 (83-223) Highly cost effective Household solar disinfection 61 (38-104) Highly cost effective Household ldflocculationl 472 (70-813) Cost effective (Highly disinfection CE at net cost of US$354) *Gross cost, excluding health cost offsets **Minimum/maximum costs; 95%CI of effectiveness

24 Expansion Path

25 The International Network to Promote Household Water Treatment and dsafe Storage Secretariat W ld H lth O i ti World Health Organization Geneva

26 Network Mission To contribute to a significant reduction in waterborne disease, especially among vulnerable populations, by promoting household water treatment and safe storage as a key component of water, sanitation and hygiene programmes.

27 Scaling Up: Litres Treated * *Excludes emergencies Clasen T (2008). Scaling up Household Water Treatment and Safe Storage. Geneva: World Health Organization

28 Scaling Up: HWTS Users * *Excludes emergencies

29 Coverage of 884 million without access to improved water supplies 60% Coverage

30 Diffusion Curves Rogers E (2003). Diffusion of Innovations (5 th ed.). New York: Free Press

31 Adoption of Household Innovations Federal Reserve of Dallas 1996

32 Scaling Up Insecticide Treated Nets UNICEF (2007). Malaria and Children: Progress in Intervention Coverage. New York: The United Nations Children s Fund

33 Special Challenges for Scaling up HWTS Belief that diarrhoea is not a disease Scepticism about the effectiveness of water quality interventions Special challenges associated with uptake Technologies shortcomings with the available interventions Need for correct, consistent, sustained use (contrast vaccines) Other transmission pathways Evidence of inequitable uptake (Olembo 2003, DeBois 2004, Rheingans 2008) Public health suspicion of commercial agenda and lack of standards governing HWTS products Orphan status of HWTS at public-sector level Lack of focused international effort and commitment

34 HWTS Policy Issues

35 Should effective HWTS be actively promoted? Pro Con Addresses major disease burden Does not improve water quantity Safe Does not generally improve access Effective Evidence of disparities i i in uptake Cost-effective Diverts resources from improving sources (?) Evidence of scalability and sustainability Affordable (by some) Potential for self-funding (through beneficiary contributions and health sector savings) Provides only an interim/short-term solution (?)

36 What HWTS is effective HWTS? Acceptability Productivity Performance (lab and field) Access/Uptake Suitable, desirable Daily production Longevity Microbiological performance Chemical performance Toxicity/adverse impact Supply chain access (procurement) Correct, consistent use Availability and uptake of consumables Minimum standards and test procedures Affordability Up-front cost Who pays? Sustainability Long-term cost Long-term use Environmental impact

37 How should JMP report on HWTS? Joint Monitoring Programme organized by WHO and UNICEF as successor to Water and Sanitation Decade Purpose Monitor sector progress toward internationally- established goals on access to water and sanitation Monitor sector trends and programmes Build national sector monitoring capacity Inform national and global policymakers on status of the sector JMP s improved water sources is officially recognized as the indicator for the MDG water target

38 JMP Core WatSan Questions Q1: What is the main source of drinking water for members of your household? Improved sources Piped water into dwelling (household connection) Piped water to yard/plot (yard connection) Public tap or standpipe Tubewell or boreholde Protected dug well Protected spring Bottled water* Rainwater Unimproved sources Unprotected spring Unprotected dug well Cart with small tank/drum Tanker-truck Surface water *Bottled water is considered an improved source of drinking water only when there is a secondary source of improved water for other uses such as personal hygiene and cooking. For those who respond bottled water to Q1, Q1A asks about the main source used by household for other purposes.

39 *Q4: Do you treat your water in any way to make it safer to drink (Yes, No, Don t Know) *Q5: What do you usually do to the water to make it safe to drink? (Record all items mentioned) Adequate water treatment Inadequate water treatment Boil (bringing water to rolling boil) Strain it through a cloth Add bleach/chlorine Let it stand and settle Use of water filter (ceramic, sand, composite, etc.) Solar disinfection * The questions are intended to gather information on water treatment practices at * The questions are intended to gather information on water treatment practices at the household level, which provides an indication of the quality of the drinkingwater used in the household. (JMP, Core Questions, 2006)

40 Global Estimates of HWTS: JMP Data 1000 Estimated Population using HWTS (54 Countries)* ns) ,81 Adequate Population (in Millio ,35 216,54 231, ,58 62,24 2,84 27,33 22,61 Type of HWT *Rosa G, Clasen T (in preparation). The global prevalence of boiling as a means of treating water in the home.

41 Microbiological Effectiveness of Boiling: Vietnam Geo Mean Source 95% CI Geo Mean Drinking 95%CI Round (115.2; 235.5) 5) (2.5; 6.2) Round (111.6; 259.3) 6.5 (4.2; 10.2) Round (75.7; ) (2.1; 3.9) Round (103.2; 191.4) 4.4 (2.9; 6.9) Round (95.1; 185.3) (2.8; 6.4) Boiling was associated with a 97% reduction in TTC, from 141 TTC/100ml in source water to 4.2 TTC/100ml in drinking water. Nevertheless, 60.5% of stored water samples were positive for TTC, with 22.2% 2% falling into medium risk ( TTC/100ml) Clasen T, Do Hoang T, Boisson S, Shippin O (2008). Microbiological effectiveness and cost of boiling to disinfect water in rural Vietnam. Environmental Sci. & Tech. 42(12):

42 Microbiological Effectiveness of Boiling: India Source Drinking Mean 95%CI Mean 95%CI p-value Round (261.5; 694.5) 6.1 (4.4; 8.3) <0.001 Round (615.4; ) 6.1 (4.4; 8.3) <0.001 Round (484.8; ) 7.2 (5.2; 9.9) <0.001 Round (566.0;1577.5) 6.0 (4.4; 8.2) <0.001 Round (144.3; 439.1) 4.0 (3.0; 5.2) <0.001 Boiling was associated with a 99% reduction in geometric mean EC, from CFU/100ml in source water to 5.8 CFU/100ml in drinking water. Still, 40.4% of drinking water samples were positive for EC, with 25.1% falling into high risk ( FC/100ml) Clasen T, McLaughlin C, Nayaar N, Boisson S, Gupta R, Desai D, Shah N. Microbiological effectiveness and cost of disinfecting water by boiling in semi-urban India. Am J. Trop. Med. Hyg. 79(3)

43 Drinking Water Ladder WHO/UNICEF JMP (2008): Progress on Drinking Water and Sanitation

44 Placing HWTS on the Water Ladder Regulated piped water supply Improved water source + HWTS Improved water source Improved shared water source Unimproved water source + HWTS Unimproved water source

45 HWTS and the MDG Water Target Unhygienic handling of water during transport or within the home can contaminate previously safe water. A high percentage of people could therefore benefit from effective household water treatmentt t and safe storage practices. Such household-levelh l l interventions can be very effective in preventing disease if they are used correctly and consistently.... The JMP is currently undertaking an investigation to explore issues related to household water treatment technologies, with a view to evaluating their potential role in providing measurable access to a safe and sustainable drinking water supply. WHO/UNICEF Joint Monitoring Programme (2008) WHO/UNICEF Joint Monitoring Programme (2008): Progress in Drinking Water and Sanitation

46 Should effective HWTS count toward the MDG water target ( sustainable access to safe drinking water )? Pro Except perhaps for regulated, piped water supplies, improved safe Evidence from boiling studies that HWTS as actually practiced by vulnerable population-- can substantially improve drinking water quality (safety) Widespread practice of boiling and other HWTS suggests potential for scalability and sustainability Some evidence that HWTS contributes toward other MDG s Con Shifts burden (and possibly more cost) of water quality to users Requires correct, consistent action on the part of householders; evidence from boiling studies suggests existing practices are sub-optimal Disparities in uptake likely to continue Does not improve quantity or generally improve access

47 Potential contribution of water supply and effective HWTS to MDG water target Quantity Quality Access Affordability Sustainability Regulated piped supply, household connection Other improved supply + HWTS Other improved supply only ? ? Unimproved Neutral + + +? supply + HWTS Unimproved Baseline supply

48 Potential contribution of water supply and HWTS to other MDGs Reduce Poverty Reduce Hunger Increase Improve Reduce Reduce Reduce Primary Gender Child Maternal Major Education Equality Mortality Mortality Diseases Regulated piped supply, household connection Other improved source + HWTS Other improved source only Unimproved source HWTS Unimproved source Baseline

49 HWTS and the MDG Water Target Helping households improve and maintain water quality at home has proven health benefits, is cost-effective, and contributes directly to meeting the Millennium Development Goals. Household water treatment and safe storage can serve as an immediate mechanism to reduce illness among the unserved.... Although there are challenges, particularly with regard to achieving widespread adoption and sustainability of the interventions, household water treatment offers a rapid and affordable way of reducing the global burden of waterborne disease. (emphasis added) MDG Task Force on Water and Sanitation (2005) Lenton R, Wright A, Lewis K (2005). Health, dignity, and development: what will it take. London: Earthscan

50 Acknowledgements CDC (S. Luby, R. Quick J. Crump, T. Chiller, E. Mintz, D. Lantagne) Proctor & Gamble (G. Allgood, B. Keswick) WHO (J. Bartram, B. Gordon, L. Haller, J. Sims, F. Properzi, R. Bos) Johns Hopkins University (M.E. Figueroa, L. Kincaid, D. Walker, S. Doocy) UNICEF (C. Brockelhurst, H. van Norden) University of Bristol (S. Gundry, J. Wright) UC Berkeley (J. Colford) University of Wales (L. Fewtrell) University of North Carolina (M. Sobsey, J. Brown) LSHTM (S. Cairncross, V. Curtis, I. Roberts, T. Rabie, L. Smith, W. Schmidt, G. Rosa, S. Boisson)