The need to learn how to succeed is urgent. Long-standing problems remain unsolved, such as the differential in health between rich and poor. Newer ones - from the AIDS pandemic to the growing toll of cardiovascular disease - threaten future generations. Among the challenges are:
- Inequality. Higher income has translated into better nutrition, health, and access to health service in much of the world. However, this progress masks an important failure: the gap in mortality, life expectancy, and disease burden between rich and poor countries and between rich and poor children within most countries. Ninety-nine percent of childhood deaths occur in poor countries, and child mortality rates within countries are highest among the poorest. In Indonesia, for example, a child born in a poor household is four times as likely to die by age five than a child born to a family in the richest segment of the population.
- HIV/AIDS. The soaring rates of HIV/AIDS have erased decades of steady health improvements in sub-Saharan Africa. An estimated 25 million people are HIV-positive in Africa. The death toll on the continent is staggering, and it has contributed to the reversal in life expectancy - now 48 years instead of an estimated 62 years without AIDS.
- High child mortality. Child mortality has declined in low- and middle-income countries, but more than 11 million children under age five die each year, 45% of them in sub-Saharan Africa and 33% in South Asia. The rate of improvement in child health has slowed dramatically in the past 20 years in countries where child mortality rates are highest - and yet most of these children die of diseases that can be treated or prevented.
- Cardiovascular and chronic diseases. Chronic diseases, and cardiovascular disease in particular, have emerged as a "hidden epidemic" in developing countries. Estimates suggest that conditions such as depression, diabetes, cancer, obesity, respiratory diseases, and cardiovascular disease will grow from about 40% of the health burden in developing countries in 2002 to nearly 75% in 2020. Responding to this impending crisis requires that the major risk factor (high cholesterol and blood pressure, obesity, smoking, and use of alcohol) be addressed through changes in diet, physical activity, and tobacco consumption.