A U.N. effort to reduce the spread of AIDS to children by encouraging HIV-positive mothers to use formula rather than breast feeding has backfired in Botswana. It has resulted in many children dying from diarrhea, pneumonia, and malnutrition, while saving few, if any, from AIDS. In the Third World, the risk of a child contracting AIDS from breast feeding is less than risks associated with formula, such as getting diarrhea and other ailments from unsterilized water used to prepare the formula. AIDS rates remain stubbornly high in Botswana, which is one of Africa's wealthiest countries (owing to diamonds), and has one of its highest HIV-rates. Meanwhile, AIDS rates are falling in neighboring Zimbabwe, which receives less international assistance. Zimbabwe's economy has collapsed. As a result of reduced living standards and lower levels of foreign aid, people in Zimbabwe have become too poor to afford multiple sexual partners, reducing the spread of AIDS.