Transcript WHO International Scheme to Evaluate Household Water Treatment Technologies UNICEF International Network on Household Water Treatment and Safe Storage 10-13 November 2014 Vientiane, Lao.

WHO International Scheme to Evaluate Household
Water Treatment Technologies
UNICEF International Network on Household Water Treatment
and Safe Storage
10-13 November 2014
Vientiane, Lao
Basis for Scheme
• Household Water Treatment
– Implementable, cost-effective approach to improved water quality
– May play an important role in protecting public health where
existing water sources are untreated, not treated properly, or
become contaminated during distribution or storage.
• Important interim solution for:
– ~ 780 million without access to improved drinking-water supplies
(http://www.unicef.org/media/files/JMPreport2012.pdf).
– Billions without access to safe and reliable drinking-water
Requires optimal choice, consistent and correct use!!!
How to make an optimal choice?
Technologies:
Physical removal (filtration, adsorption, sedimentation)
Chemical (chlorine, iodine, silver)
Disinfection by heat (boiling, pasteurization)
Ultraviolet (UV) radiation
Solar disinfection
Combination
Emerging technologies
Options! Options! Options!
How to choose: basis for Scheme
• Locally relevant performance specifications needed for
decision-making for selection of technologies or approaches
– Information is not always available
• To realize health gains associated with HWT
– HWT technologies must sufficiently reduce pathogens to result
in significant health gains
– Technologies must reach and be consistently and correctly
used by the populations most at risk for waterborne disease.
• Until recently: No international specifications to evaluate
performance claims of HWT product against a health-based
performance benchmark existed.
WHO Recommendations (WHO, 2011)
• WHO established an international evaluation scheme for HWT to
fill the need for rigorous health-based assessments of HWT
technologies (December 2012)
• First document that sets forth global criteria to
evaluate microbiological performance of HWT
(June 2011)
• WHO Scheme to Evaluate Household Water
Treatment (HWT) Technologies
• “The Scheme”
WHO Recommendations and the Scheme
Objectives:
• Promote and coordinate independent and consistent testing for the
evaluation of household water treatment products based on WHO
criteria
• Support national governments building technical capacity of
research and laboratory institutions; especially in applying WHO
Guidelines on Drinking-water Quality.
Aim:
• Guide WHO Member States and procuring UN agencies in the
selection of technologies and support national governments in
evaluation related functions.
Why a WHO International Scheme?
• Many countries do not have the capacity to evaluate HWT
based on WHO recommendations
• Ensures criteria are appropriately adopted
• Effective mechanism to build national capacity
• WHO, global authority on public health
• Precedence: WHO Pesticide Evaluation Scheme, WHO
Evaluation of Rapid Malaria Diagnostic Tests
Scheme Scope
Products included in the Scheme
Household water treatment technology (definition)
Products used in households or similar settings to remove
microbiological water contaminants that may pose health risks.
Priority for testing:
• Low-cost
• Appropriate for developing country settings
• Generally “free standing” products
• Serve a limited number of individuals each
day.
Scheme Components
Laboratory Testing
Evaluation based on laboratory testing
• Based on harmonized test protocol
• http://www.who.int/household_water/scheme/HarmonizedTestProtocol.pdf?ua=1
• Microbiological reduction/inactivation performance
specifications (not chemical)
• Tiered approach: series of health-based performance targets
Subsidized testing – funding secured for Scheme
• Subsidy subject to availability of funds
• Criteria: size and capital resources of manufacturer;
origin/location of manufacturer; local need; cost/liter treated
Scheme Components
Designated Testing Laboratories
Selection criteria:
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•
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Institution with formal WHO relations
Not-for-profit, ISO certified
Stable income of core activities
Strictly adhere to harmonized test protocols/plans
Agree to WHO ownership of test results
•
http://www.who.int/household_water/scheme/laboratories/en/
Currently designated:
•
NSF International (USA); KWR (Netherlands)
•
Aim to designate labs in different geographic regions
Scheme Components
Independent Advisory Committee (IAC)
• Advisory body to WHO on the Evaluation Scheme.
• Experts with demonstrated commitment to advancing public
health
• Goal: attain an adequate technical distribution of expertise in
drinking water quality, microbiology, water treatment
technology and/or regulation, geographical and gender
balance.
• http://www.who.int/household_water/scheme/IAC/en/
Scheme Components
Performance - Tiered approach
WHO HWT: Series of health-based performance targets
which allows for incremental improvements
Highly protective:
Protective:
Limited protection:
10-6 DALY/person/year
10-4 DALY/person/year
Meets “protective” for two
classes of pathogens
Based on Disability-Adjusted Life year (DALY)
Target pathogens: viruses, bacteria and protozoa
Basis for assessing performance
Rating
Highly
protective
(10-6 DALYs/ P/yr)
Protective
(10-4 DALYs/ P/yr)
Limited
protection
Log10 reduction:
Log10 reduction:
Log10 reduction
bacteria
viruses
protozoa
≥4
≥5
99.99% 99.999%
≥2
≥3
99%
99.9%
≥4
99.99%
≥2
99%
Achieves “protective” target for two classes of
pathogens
Scheme Procedure
Invitation for expression of interest
• Manufacturers to submit detailed information on product
WHO screening of dossiers
• WHO will review with input from the Independent Advisory
Committee and determine which products are eligible for testing
Testing (or evaluation of exiting data)
• Products and payment for testing sent to laboratories
• Specific test plans, based on harmonized test protocol,
developed by laboratories in consultation with manufacturers
Scheme Procedure, contin
Testing Results and Reporting
• Laboratory will report results to WHO
• WHO with advice from IAC will determine level of performance
• Summary of ALL results posted on WHO website
Use of Information
• Manufacturers can discretely list performance level achieved in
technical material addressed to water and health professionals
• May not use WHO name or logo in any manner
Maintenance
• Manufacturers update WHO on changes in product/manufacturing
Challenges and Conclusion
• Starting simple; 2 laboratories and
technically advanced protocols
• Future work on simplifying protocols and
building national laboratory capacity
• Linking evaluation to new and innovative
products
WHO/ M Montgomery
• Optimizing performance in tandem with
achieving consistent and correct use
HWT only has health impact if used consistently
and correctly by at-risk populations!
More information
Visit Scheme Webpage:
http://who.int/entity/household_water/scheme/en/
Contact: Nikki Beetsch
Water, Sanitation, Hygiene and Health
World Health Organization
[email protected] or [email protected]