mortality. Although there remain substantial inequalities in health between countries, regions, socioeconomic groups, and individuals, 85 percent of children born in the developing world now survive to age 5 (Leon and Walt, 2001). Overall, aside from some countries with very high prevalence of HIV/AIDS, young people in developing countries are entering adolescence healthier than ever and with a better chance of surviving to old age. Improvements in the health environment are important not only for the immediate survival chances of young people, but also as they affect other aspects of the transition to adulthood: healthy individuals make better students, more productive workers, more active community members, more attractive marriage partners, and better parents and caregivers than those who suffer from poor health.
In sub-Saharan Africa, the greatest immediate threat to adolescents’ health relates to the HIV/AIDS pandemic. Globally, almost 12 million people ages 15-24 were estimated to be living with HIV/AIDS in 2002, and about half of all new infections are now occurring among this age group (Summers, Kates, and Murphy, 2002; UNAIDS, 2002). Until recently, antiretroviral drugs have been largely unavailable in developing countries. As a result, those with HIV/AIDS have a relatively short life expectancy. In the future, with expectations that these drugs will become increasingly available at reasonable cost, young people infected with HIV in developing countries will have a greater chance of treatment and thus living a longer and healthier life than they do now.
Adolescence is a time when many people first engage in sexual activity, potentially increasing their risk of unplanned pregnancy and unsafe abortion as well as of sexually transmitted infections (STIs), including HIV/AIDS. Delays in the age of marriage, however, have not resulted in a decline in the age at first sex; quite to the contrary, in most countries it appears that because of delays in the age of marriage there has been no change or a delay in the percent having first sex before the age of 18 (see further discussion in Chapter 4). However, even in places where there has been no decline in the age of first sex, sex may have become riskier than in the past because of the heightened risks associated with the AIDS epidemic in places where it has been growing.
HIV/AIDS is now the leading cause of death among 15-29-year-olds in the poorest and highest mortality countries. (Injuries and noncommunicable diseases remain the primary sources of deaths and are much more important than HIV/AIDS in the low- and medium-mortality developing countries.) However, in high-mortality countries and among women ages 15 to 29, maternal conditions are an equally important cause of loss of healthy years of life. In the context of risks of HIV infection, as well as other undesirable reproductive health outcomes (STIs and unwanted pregnancies), the availability of family planning and reproductive health ser-