Pub. date: 2008 | Online Pub. Date: November 27, 2007 | DOI: 10.4135/9781412953948 | Print ISBN: 9781412928168 | Online ISBN: 9781412953948 | Publisher:SAGE Publications, Inc.About this encyclopedia
Urban Health Issues
Sandro Galea & Danielle C. Ompad & David Vlahov
Demographic trends suggest that there is an urgent need to consider the health of urban populations. Cities are becoming the predominant mode of living for the world's population. According to the United Nations, approximately 29% of the world's population lived in urban areas in 1950. By 2000, 47% lived in urban areas, and the United Nations projects that approximately 61% of the world's population will live in cities by 2030. Overall, the world's urban population is expected to grow from 2.86 billion in 2000 to 4.94 billion in 2030. As the world's urban population grows, so does the number of urban centers. The number of cities with populations of 500,000 or more grew from 447 in 1975 to 804 in 2000. In 1975, there were four megacities with populations of 10 million or more worldwide; by 2000, there were 18, and 22 are projected by 2015. Most cities are in ...