05/06/2025
The developing countries differ from one another culturally, socially, and economically, but what they have in common is a low average income per person, with large percentages of their populations living at or below the poverty level. Although most have a small elite class, living mainly in the cities, the largest part of their populations live in rural areas. Urban regions in developing and some developed countries in the mid- and late 20th century developed pockets of slums, which were growing because of an influx of rural peoples and immigrants. Slums persisted into the 21st century, though newer, cheaper construction techniques greatly facilitated the development of affordable housing, alleviating some housing problems in densely populated places such as New York City and cities in India. Nonetheless, many urban areas are simply overcrowded, which is problematic for maintaining public health. For lack of even the simplest measures, vast numbers of urban and rural poor die each year of preventable and curable diseases, often associated with poor hygiene and sanitation, impure water supplies, malnutrition, vitamin deficiencies, and chronic preventable infections. The effect of these and other deprivations is reflected by the finding that in the 1980s the life expectancy at birth for men and women was about one-third less in Africa than it was in Europe; similarly, infant mortality in Africa was about eight times greater than in Europe. The extension of primary health-care services is therefore a high priority in the developing countries.
