regions, such as China, coming very close to the low-fertility world of the more wealthy countries and all regions except one showing remarkable declines in fertility.
The one exception is sub-Saharan Africa, but fertility rates in Africa have now begun to decline.
Changes in life expectancy are obviously brought about by changes in particular age-specific, cause-specific mortality rates. As you are aware, the greatest engine of life expectancy increase is infant and child mortality decrease. In 1960 there were many countries in which more than 17.5 percent of the children born alive never reached the age of five. Today there are fewer and the very highest infant and child mortality patterns have become primarily an African phenomenon.
Clearly, the challenges remain great, the inequities remain very large, and there is absolutely no room for complacency. As we think of those challenges, of the dramatic progress made in the last four decades, and of the progress that still needs to be made in the decades leading up to 2020, we first have to remind ourselves that the major influences on population health are not health professionals and do not lie within the mandate of the health sector. This is a sobering thought.
Those of us who work in health and the health sector need to bear in mind that the levers in our hands are not the most powerful ones. The most powerful levers are four. First, reduction of poverty at the national level, the community level, the family level, and the individual level has been and will continue to be the greatest engine for health improvement and for fertility reduction.
Second, improvements in education will go hand-in-hand with that, particularly for girls' education. Despite a decade of giving lip service to the education of women, disparities around the world between the education of boys and girls remain wide.
Third, fertility decline will make an important contribution to the improvement of health, and the improvement of health will make an important contribution to fertility decline.
Last, there is the environment—not those aspects of the environment that the green movements in this country and elsewhere like to emphasize. Not air pollution, global warming, the ozone layer, or biodiversity. In health terms, these are trivial. I refer here to the domestic environment—the water supply, sanitation, indoor air pollution, and drainage in and around homes—because these things have a large influence on the health of the majority of the world's population. As they improve, so will health improve.
Now, curiously enough, when a team of people gathered in 1991 and 1992 at the World Bank to write what became the 1993 World Development Report entitled Investment in Health, they discovered to their amazement that there was no map of mortality for the world. When I talk about a map of mortality for the world, I mean a disciplined statement of cause of death by region, by gender, and by age. If you surveyed experts in various parts of the World Health Organization about particular causes of death, and you asked