Global Water Sanitation and Health: What this Course is about

Mark D. Sobsey

University of North CarolinaDepartment of Environmental Sciences and Engineering

Sobsey@email.unc.edu

Kofi Annan United Nations Secretary-

General“We shall not finally defeat AIDS,

tuberculosis, malaria, or any of the other infectious diseases that plague the developing world until we have also won the battle for safe drinking-water, sanitation and basic health care.”

Perc

ent o

f tot

al b

urde

n (w

ithin

regi

on)

1% -

5% - Water, sanitation and hygiene (5.5%)

Lead

Underweight

Indoor air (3.7 %)

Ambient air Occupational injuries

Developing countries(high mortality)

Developed countries

Occupational risks

Alcohol Tobacco

Overweight

Lead

Unsafe sex

Tobacco

Climate change

Alcohol

Ambient air Water, sanitation and hygieneOverweight Unsafe sex

Physical inactivityZinc deficiency

Global Burden of Disease Attributable to Selected Major Risk Factors

Global Burden of Poor Water, Sanitation and Hygiene (WSH)

• 1.1 billion people (~17% of the population) lack access to improved water– tap water in the house or yard from public distribution

systems, protected wells and springs, public stand posts, rain water collection; 17% of world population

• 2.6 billion (42% of population) lack access to basic sanitation– sewerage, on-site septic waste treatment system, latrine

• 1.8 million people die every year from diarrheal diseases (including cholera); 90% are children under 5, mostly in developing countries.

• 80% of the population without access to drinking-water are rural dwellers, but future populations will be mainly urban• Peri-urban slums are among the most underserved and

unsanitary places on earth

Lack of WSH = Disease and Poverty

• Inadequate water supply

• Unsafe water resources

• Inequitable access

• Time, financial cost

• Disease burden

• Health care costs

POVERTY

WSH = An Engine for Development and Productivity

• Improved water supply

• Safe water resources

• Universal access

• Time, financial savings

• Averted disease costs

• Healthy populations

Development

UN Millennium Declaration

Overall Goal: Poverty Reduction

Millennium Development Goals

Goal 1 Eradicate extreme poverty and hungerGoal 2 Achieve universal primary educationGoal 3 Promote gender equality and empower womenGoal 4 Reduce child mortalityGoal 5 Improve maternal healthGoal 6 Combat HIV/AIDS, malaria, and other diseasesGoal 7 Ensure environmental sustainability

•Target 9: Integrate the principles of sustainable development into country policies … reverse loss of environmental resources.•Target 10: Halve by 2015 the proportion of people without sustainable access to safe drinking water and basic sanitation•Target 11: improve the lives of at least 100 million slum dwellers

Goal 8 Develop a global partnership for development

What a lot of this Course will be about:Five F’s of WSH

• Feces

• Fingers

• Flies

• Fields/Food

• Fluids

• Fomites

Water Treatment

Human Sanitation:Fundamental but Often Lacking

• Excreta management and disposal

• Hygiene behaviors– Handwashing

• Safe water

Sanitation: Our Biggest Failure• Our sanitation systems

don’t work well and result in pathogen release

• Whether community or on-site, they all fail or have serious deficiencies

• Sanitation is one of the biggest technological gaps we have globally

• Pathogens go everywhere as a result

Roman latrine

Latrine VIP latrine

Inferior/No Community Wastewater Treatment Systems

Untreated/poorly treated wastewater is discharged to land or natural waters

Water, Disease and Health• Water-borne

– Exposure mainly by ingestion of contaminated water– Primarily enteric diseases transmitted by the fecal-oral

route

• Water-washed– exposure is reduced by water use for personal and

domestic hygiene: washing (clothes, floors, other household chores), bathing & other personal hygiene

• Water contact and water vector-borne– Exposure by skin contact with infested water

• Ex: schistosomiasis– Exposure to water habitat "insect vector" diseases

Helminth (Worm)(eggs shed in feces)

>30 microns

BACTERIUM~ 1 µM

The Microbial World: Types and Sizes of Microbes

NorovirusHepatitis A&ERotavirusesPolio-/enteroviruses

CholeraDiarrheaTyphoid feverDysentery

Amebic dysenteryGiardiasis ( bever fever)

(Ascaris lumbricoides)

Waterborne Pathogens Come Primarily from Feces by Various Routes of Exposure

Excreta from humans and animalsExcreta from humans and animals

HumanHuman

ShellfishShellfish CropsCrops AerosolsAerosols

Oceans andEstuaries

Oceans andEstuaries

Rivers andLakes

Rivers andLakes IrrigationIrrigation

Solid WasteLandfills

Solid WasteLandfillsSewageSewageLand

Runoff

LandRunoff

RecreationRecreation WaterSupply

WaterSupply

GroundwaterGroundwater

Adapted from Charles P. Gerba et al. 1975

Spinach!E. coli

Issues in Water and Health

• Quality

• Quantity

• Access

• Habitat and Ecology

• Resources and Management

• Economics

• Behavior and Beliefs

Analyzing the Role of WSH in Reducing Disease

Recent meta-analysis shows major impacts by

• Hygiene• Sanitation• Water quality• Water supply

Comparison of Impacts of WSH Interventions: Fewtrell et al. 2005 vs. Previous Studies

All Studies Good Studies

• Water quality interventions (POU water Rx) was more effective than previously thought• Multiple interventions (combined WSH) were not more effective than single interventions (?)

Handwashing Hygiene to Prevent Disease

• Handwashing with soap and water after contact with fecal material can reduce diarrheal diseases by 35% or more

Source: Almedom et al. 1997

Piped and Non-Piped Water Supplies• Most people lack piped water

– They collect water or have it delivered

• Sources are often contaminated (UNSAFE!)• Piped water is often contaminated

– Classified as “improved” but UNSAFE!

• Collected, stored water often becomes contaminated in the home (UNSAFE!)

• Water is often not treated – used directly• Boiling is widely practiced, but……

– Disadvantages: cost, inconvenience, no residual protection (gets recontaminated in use!), environmental degradation (deforestation), air pollution (health effects)

Barriers against Microbial Contamination and Waterborne Disease

• Collect from a safe source• Store it with contamination safeguards:• Treat water to reduce microbial contamination

– Physical treatments:• Heat, sunlight (heat + UV), UV lamp radiation & filtration

– Chemical treatments (disinfection): • chlorine

– Combined physical-chemical treatments:• coagulation-flocculation-chlorination (“conventional Rx”)

Behavioral and Educational Components of WSH Interventions

Increase awareness of the link between the 5Fs and disease and the benefits of appropriate hygiene behaviors

Behavior change techniques: • social marketing• community mobilization• motivational interviewing• communication• education

World Health Organization Health-Risk Based Framework

• Risk-based framework• Source-to-consumer

management approach• Establishes health based-targets

for performance• Can set acceptable level of

risk appropriate to setting and population

– Establish and carry out Management Plans

– Independent surveillance• Integrated. Consistent across,

compatible with and applicable to all WSH measures

These principles apply to all types of WSH measures

WSH, Addressing the Global Burden of Disease by Working towards Meeting the MDGs:

Still Plenty to Do

• Research• Implementation/Dissemination

• Communication• Advocacy• Finance• Policies

• Diplomacy and Politics

Celebrating Water for LifeThe International Decade for Action

2005 to 2015