AIDS cases have also been disproportionately reported among African Americans and Hispanics/Latinos (Selik, Castro, and Pappaioanou, 1988), and this excess risk for AIDS has increased as the epidemic has progressed. African Americans and Hispanics/Latinos compose approximately 20 percent of the U.S. population. Early in the epidemic, 42 percent of those with AIDS were African American or Hispanic/Latino; by 1993, that proportion had reached 48 percent. The analysis of this excess risk for AIDS has required that researchers develop specific hypotheses regarding the role of race and ethnicity as explanatory factors in HIV infection (Osborne and Feit, 1992). Little support has emerged for biological explanations of excess risk for infection. More support has emerged for social hypotheses that examine race/ethnicity and socioeconomic status as factors in the organization of interpersonal networks within which people have sex or use drugs (Neaigus, Friedman, Curtis et al., 1994; Potterat et al., 1985; Wallace, 1988).
The number of AIDS cases reported in the United States has grown rapidly, surpassing 100,000 in 1988, 200,000 in 1990, and 300,000 in 1992. A comparison of the second 100,000 cases with the first demonstrated some of the trends of the epidemic. For example, while the first set of cases were reported between 1981 and 1988, the second set of cases were reported in the two-year period from 1988 to 1990. There was a larger proportion of cases attributable to heterosexual transmission in the second 100,000 than there was in the first 100,000. The proportion of cases among African American and Hispanics/Latinos increased from 42 percent to 48 percent of cases. Among the first 100,000 people with AIDS, 9 percent were women, while women represented 12 percent of the second 100,000 (CDC, 1992a).
Sixty percent of adults and 53 percent of children diagnosed with AIDS have died. In November 1993, the Centers for Disease Control and Prevention reported that by 1992 HIV infection had become the leading cause of death for men aged 25 to 44 and the fourth leading cause of death for women in this age group. AIDS is the cause of 19.9 percent of deaths among men and 7.3 percent of deaths among women in this age group (Figure 2.1). Factors such as socioeconomic status and access to health care are thought to affect length of survival and quality of life after diagnosis (Curtis and Patrick, 1993).
As AIDS has spread in numbers and through risk groups, it has also spread geographically. From the major urban centers where it was first identified, AIDS was disseminated through hierarchical