Population projections assume lower fertility, Greater control of HIV.
The projected 2.5 billion increase by mid-century is the equivalent of the entire world population of 1950, and developing countries will bear nearly all the net growth, according to the UN. The total population in these countries is projected to rise from 5.4 billion in 2007 to 7.9 billion by 2050. The industrialized world is expected to maintain its existing population of 1.2 billion through 2050--even with anticipated net immigration of 2.3 million people annually--and to nearly double its population aged 60 and over.
In these projections, fertility in less-developed countries is assumed to decline from 2.8 children per woman in the 2005-10 period to 2.1 in the 2045-50 period (roughly the number that would eventually stabilize a population with no net migration). UN demographers assume an even more dramatic drop in fertility in the 50 least-developed countries, from 4.6 children per woman to 2.5. If the fertility rates observed in 2000-05 were to remain the same, they note, the population of the less-developed regions would increase to 10.6 billion instead of 7.9 billion; in other words, without continued reductions in fertility, the world population could increase by twice as many people as were alive in 1950.
The UN projections also assume a major increase in the share of AIDS patients who receive antiretroviral therapy, as well as growing success in slowing the spread of HIV. They assume that by 2015,31 of the most AIDS-affected countries will manage to provide antiretroviral treatment to at least 70 percent of their infected populations. In countries less affected by the pandemic, treatment levels are expected to reach only 40 to 50 percent of those infected by 2015. Demographers also assume that patients receiving treatment will survive 17.5 years on average, compared with the 10 years expected for untreated patients-a measure of the effectiveness of antiretroviral therapy in prolonging life.
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|Title Annotation:||EYE ON EARTH|
|Date:||Jul 1, 2007|
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