African Water Development Report 2006 - United Nations Economic ...

No other type of action has a greater overall impacton national development and public healththan does the provision of safe drinking waterand proper disposal of human excreta. The directeffects of improved water and sanitationservices on health are most evident in the caseof water-related diseases, which arise from theingestion of pathogens in contaminated water orfood and from insects or other vectors associatedwith water. Improved water and sanitation canreduce morbidity and mortality rates of some ofthe most serious of these diseases by 20 per centto 80 per cent (WHO Fact Sheet, 1996).Benchmarks for Health Expenditures,Services and Outcomes in AfricaA WHO study in 2000 found that although mostpost-independence African countries achievedremarkable improvements in health conditionsduring the last four decades, Africans still sufferfrom some of the worst health problems in theworld and have the highest mortality and fertilityrates. In 1990, the median age of death wasestimated at five years. African countries faceenormous difficulties in mobilizing and managingresources to improve public health. Two thirdsof all the countries in Africa are classified as lowincome and have limited potential to mobilize resources.Nearly all have weak health managementsystems. The challenge of a massive burden of disease(predominantly water-related diseases) fromlargely preventable or treatable conditions thatprecede the epidemiological transition, the emergenceof new diseases and such health problemsas AIDS and drug-resistant tuberculosis, togetherwith political changes, increase the need for moreinformation for management and accountabilityof the health sector in African countries. Goodinformation is vital to making intelligent choicesabout strategies and investments in health. Yet inmuch of Africa, information that would be criticalto policy makers, health systems managers andpublic consumers of health services is often notavailable, despite increasing emphasis on data collectionin many countries. The findings are summarizedbelow (WHO, 2000).WATER FOR MEETING BASIC NEEDSBox 5.3Health-adjusted life expectancy (HALE) is defined as the number of years that a newborn can expect tolive in full health based on current rates of ill-health and mortality. Healthy life expectancy combines informationon mortality and disability, making it a valuable policy tool for assessing health burdens internationally. The datacan assist in identifying the major causes of poor health for a particular group; it can also show variation in levelsof health across a population and trends in levels of health over time. The data are for the year 2002. WHOpublished the first country-level dataset on health adjusted life expectancy (HALE) for 191 countries in 2001.Since that time, WHO has been working jointly with member States to refine HALE estimates. As a result,the estimates for 2002 are not directly comparable with the previously published estimates for 2000 or 2001.WHO publishes The World Health Report annually. This dataset represents the culmination of more than fifteenyears of work by WHO to measure severity-weighted incidences of ill-health. Estimates are grouped by age,sex, and epidemiological subregions of a particular population. Calculation of HALE is a multi-step process. First,researchers must determine, on average, the number of healthy years “lost” in an individual life due to a specificillness or injury:YLD = Prevalence x Duration x DWwhere YLD is years lost due to disability for a particular illness or injury,Prevalence is the percentage of the population affected by the disability. Duration is the average time period thatan individual is in ill health, and DW is the disability weight. The disability weight is an index number between 0and 1 indicating the severity of the disability.After the years lost due to disability (YLDs) are calculated for 175 groups of illnesses and accidents, the cumulativeimpact of all disabilities is subtracted from ordinary life expectancy to calculate healthy life expectancy:HALE = Ordinary Life Expectancy - Sum of YLDs for all disabilities95