Data: Population Bomb

In a 1989 book review for the Los Angeles Times, National Park Service biologist David M. Graber notoriously opined that humans had "become a plague upon ourselves and upon the Earth" and that "some of us can only hope for the right virus to come along." The United Nations latest population projections indicate that Graber's "right virus" may have come along: HIV. (See "Wild Idea," page 19.)

According to the U.N.'s latest population projections, the world of 2050 will have 8.9 billion people. Just two years ago, the U.N. had estimated a population of 9.4 billion. The drop is due to declining worldwide fertility, better census data, and the massive effect of AIDS in Africa, the continent with the highest fertility rates and lowest life expectancies. The U.N. hasn't calculated the contribution of each factor, but the human devastation of AIDS is clear. Botswana, where more than one in five adults is infected with HIV, will have 20 percent fewer people in 2015 than otherwise. Zimbabwe, the country with the second highest infection rate, will have 19 percent fewer people in 2015. In the 29 African countries hardest hit by AIDS, life expectancy at birth is currently 47 years, seven years shorter than would be expected in the absence of AIDS.

Life Expectancy at Birth in Countries Hardest Hit by AIDS
Source: United Nations 1985-90 2010-15
Botswana (% of adults HIV+: 22.09) 62.5 48.9
Zimbabwe (% of adults HIV+: 21.52) 56.8 50.4
Zambia (% of adults HIV+: 16.62) 50.4 51.5
Namibia (% of adults HIV+: 16.12) 56.0 41.5
Malawi (% of adults HIV+: 12.51) 45.3 48.1
Mozambique (% of adults HIV+: 11.92) 46.2 39.6
South Africa (% of adults HIV+: 11.80) 57.9 47.2
Rwanda (% of adults HIV+: 11.16) 48.2 47.1
Kenya (% of adults HIV+: 10.43) 57.5 51.0