enhances the probability that HIV infection will be passed between sexual partners (Cohen, 1998). Data on the prevalence of other STIs among young people are scarce, and trends are virtually impossible to discern. Existing studies, however, give the impression that a substantial minority of young people may contract STIs. For example, studies in eight countries of various populations ranging in age from 12 to 24 show that between 3 and 12 percent of males and 1 to 14 percent of females had ever experienced an STI (Brown et al., 2001). Furthermore, WHO estimates that, globally, one in three new infections occur in people under the age of 25 (World Health Organization, 1999a).
Trends in the proportion of young people with HIV/AIDS are not available for most countries.6 For some countries in sub-Saharan Africa (plus Haiti), however, there are now sufficient surveillance data gathered from young women attending antenatal care to begin to see some positive changes taking place. Of the 18 countries for which there are adequate data, there is evidence of stability in HIV prevalence in seven countries and of falling prevalence in eight countries (Joint United Nations Programme on HIV/AIDS [UNAIDS], 2004; personal communication, 2004). The current estimates of HIV prevalence among pregnant women ages 15-24 in these countries ranges from around 3 percent in Haiti to 33 percent in Botswana. In three countries—Lesotho, Mozambique, and Swaziland—the available evidence suggests that prevalence continues to rise.
Future trends in HIV/AIDS among young people depend on a range of factors, but basic knowledge about the disease and ways to prevent it are among the most crucial (see Box 4-1 for further discussion of the future impact of HIV/AIDS on today’s young people). The proportion of females ages 15-24 who are unaware that a healthy-looking person can be infected with HIV/AIDS averages 46 percent in 73 developing countries with appropriate surveys, mostly surveys taken as recently as 2000. The level of misinformation is higher than average in sub-Saharan Africa (51 percent across 39 separate surveys), and still higher in Central Asia and the Caucasus (60 percent across 7 surveys). Only in the Caribbean does the lack of awareness fall below 10 percent (Joint United Nations Programme on HIV/AIDS [UNAIDS], 2002). In virtually every country in which comparable data on young men are available, the percentages who are unaware are lower for males than females (UNICEF, 2002). While young people may be unaware of certain dangers, they also see dangers where they do not exist. In surveys