标题：Contribution of Water Pollution From Inadequate Sanitation and Housing Quality to Diarrheal Disease in Low-Cost Housing Settlements of Cape Town, South Africa
摘要：Objectives . We investigated the effects of failing sanitation, poor housing conditions, and fecal pollution in runoff water on the health—particularly the incidence of diarrheal disease—of residents of low-cost housing settlements in Cape Town, South Africa. Methods. In November 2009, we conducted a cross-sectional survey with structured interviews in 4 communities (n = 336 dwellings; 1080 persons). We used Colilert defined-substrate technology to determine Escherichia coli levels in runoff water samples taken from the study communities. Results. Almost 15% of households disposed of soiled products in storm water drains and 6% disposed of soiled products in the street. In only 26% of the dwellings were toilets washed daily. Approximately 59% of dwellings lacked a tap near the toilet for hand washing, and 14% of respondents suffered 1 or more attacks of diarrhea in the 2 weeks preceding their interview. E.coli counts of runoff environmental water samples ranged from 750 to 1 580 000 000 per 100 milliliters. Conclusions. A holistic and integrated approach is needed to improve housing quality and sanitation among Cape Town's low-income citizens. Shelter, access to adequate potable water, and sanitation are basic human needs that pose serious challenges to developing countries. 1 In South Africa, these challenges are greatly heightened by the rapid rate of urbanization driven by low-income migrants from rural areas and the rapid expansion of informal urban settlements. 2 South Africa is facing a low-income housing crisis, with the current unmet need estimated at more than 3 million units. 3 South African housing policy mostly promotes state-funded home ownership for the poor. 4 One of the 6 principles of the South African government's low-cost housing scheme, now called the Breaking New Ground initiative (formerly the Reconstruction and Development Program) is to improve the living conditions and therefore the health of the recipients of the new houses. 5 Low-cost housing units are usually allocated to residents of makeshift dwellings in the many informal settlements surrounding cities and towns. Unfortunately, ownership of a new formal house has not been accompanied by any increase in recipient income in these resettlement programs. The owners of low-cost houses exploit one of the few resources they have—space—by allowing others to build informal structures (called “shacks” by the inhabitants) in their backyards, creating rental income. This practice has greatly increased population density in low-cost housing communities, placing infrastructure under significant strain. 6 The interrelated effects of water quality, human waste disposal, and health status, especially disease transmission via the fecal–oral route, are well established. 7 , 8 Improved water quality and sanitation confer both health and nonhealth benefits. 9 Water has 2 contrasting roles affecting health: it can be a disease vector by carrying pathogens, and it can prevent disease when it is available in sufficient quantity for personal and domestic hygiene. Indirect effects related to health include, for example, improved quality of life and decreased medical expenses. 8 Diarrheal diseases are an important cause of morbidity and mortality in low- and middle-income countries. In these countries, such diseases kill an estimated 4.9 of every 1000 children younger than 5 years 10 , 11 and are the third most frequent cause of death and the third greatest contributor to the burden of disease in this age group, constituting 8.8% of all disability-adjusted life years. 12 , 13 The World Health Organization estimates that there are 0.75 cases of diarrhea per person worldwide annually. 13 In South Africa, diarrheal diseases account for 3.1% of total deaths—the eighth most frequent cause of death in the country. 12 , 14 Problems of environmental pollution of living space and of domestic hygiene are almost always related to poverty and sanitation. 15 Pathogens, especially enteric pathogens, are transmitted at household level through a complex set of interdependent pathways, such as contaminated food and water, poor waste disposal that contaminates living spaces, and intricate household and community person-to-person interactions. 16 We investigated the interplay of inadequate housing and poorly functioning sanitation with ill health and environmental pollution in formal low-cost housing settlements in Cape Town, South Africa.
