If trends continue, by 2015 the regions where people are least likely to have basic sanitation will be sub-Saharan Africa (only 31 percent will have adequate sanitation), southern Asia (36 percent) and Oceania or islands of the tropical Pacific Ocean (53 percent). According to the World Health Organization, 1.1 billion people in the world relieve themselves in open areas.
The World Health Organization estimates that at any given moment, half of the developing world's people are sick from diseases associated with dirty water and bad sanitation.
Getting past the "first-grade jokes" is not easy, said Christiana Peppard, professor of theology, science and ethics at Fordham University, but "this problem has existed for such a long time and so many people suffer from it."
Besides the heavy human toll, there's an economic cost: The World Bank says that lack of proper sanitation results in $260 billion losses a year due to health costs and loss of output.
People who are unable to find adequate sanitation often use clean water supplies for defecation, which becomes contaminated and spreads disease.
The hardest hit are children. Diarrhoeal diseases, stemming from improper sanitation, are the second-leading cause of deaths—respiratory diseases are first—among the young in developing countries. Some 2,000 children die each day from poor sanitation and contaminated water supplies, according to Unicef.
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Women are also at special risk from improper sanitation, said Peppard, who pointed out that many women wait until nighttime to relieve themselves in the fields because they risk sexual attack if they're spotted in seclusion during the day.
"And a lot of young girls don't go to school because there are no facilities to take care of their menstrual cycles," she added. "They can't get an education because there's no real sanitation."