The past fifty years have seen a world population shift totally unprecedented in history. In 1950 only one quarter of the world’s people lived in cities. In the year 2000, that figure was over 50%. This means that in the span of a half-century over 1.5 billion people, mostly the poor in developing countries, moved from rural areas to rapidly growing cities. A number of mega-cities (those over 15 million) have resulted, the majority in developing countries. Most of these internal migrants are desperately poor. They move in order to find work and a better life for themselves and their families. Cities offer the promise of a way out of misery and poverty, opportunities for education, employment and expectation of better health. This promise is not fulfilled. Those who go to the city end up being squatters, with no title to the land, and no services. There is often no work. Few jobs can support a family. People live under squalid conditions. Their houses are crowded together, built out of plastic sheeting and scraps of metal, and lack adequate cooking facilities, latrines, and potable water. The people have no political recognition, and are either ignored or persecuted by government forces.This move to the cities has a particularly dramatic impact on health. The combination of overcrowding and the lack of potable water and sanitation render the population susceptible to epidemics of contagious disease. The Aedes mosquitos that carry Dengue Fever and Hemorrhagic Fever thrive in stagnant pools throughout the slums. Diarrhea and respiratory illnesses are more common. Despite closer theoretical proximity to health care, mortality in infants and children under five is actually higher among the urban poor than it is in the countryside. There is also disintegration of the extended family and kinship support system usually available in rural areas. Long standing cultural traditions are often lost. This lethal combination causes severe psychological stress and family breakup. Because there is no money to buy food and no place to grow crops, malnutrition, particularly in children is rampant. Ironically, lifestyle changes, including decrease in exercise and increased consumption of junk food contribute to a major increase in obesity, diabetes and cardiovascular problems.
Some government health systems have attempted to respond to this complex crisis, but are overwhelmed by the scope of the problem and the costs involved. Other governments remain indifferent. In 1992 the UN Conference on Environment and Development, more commonly known as the Earth Summit, formed a committee that addressed the global issue of urbanization, and formed a plan for human settlement development. This committee continues to meet every four years, but has had little impact on the problem. As health volunteers, we need to be aware of global urbanization and the marked effect it has on the health of the countries we serve. We also need to consider an increasing emphasis on supporting local health systems and serving the health needs of these urban poor.
Roger Boe MD
References:
Patel, R. B. et al. Urbanization—An Emerging humanitarian Disaster. NEJM 2009; 361:741-43.
Moore, M. et al. Global Urbanization and Impact on Health. Int J. Hyg. Envirn. Health 2003; 206:269-278.