Epidemiology of HIV Infection and AIDS in the United States

Abstract

By the end of 1987, nearly 50,000 cases of acquired immunodeficiency syndrome (AIDS) had been reported since 1981, 20,745 in the past year alone. Black and Hispanic adults and children have reported rates 3 to 12 times as high as whites. This can be largely attributed to higher reported rates in black and Hispanic intravenous (IV) drug abusers, their sex partners, and infants. In 1986, reported AIDS deaths increased adult male and female mortality in the United States by an estimated 0.7 and 0.07%, respectively, with much greater increases in selected age groups or areas of the country. The greatest variation in infection with the human immunodeficiency virus (HIV) (0 to 70%) has been found in surveys of IV drug abusers, while surveys of homosexual men reveal infection rates of 20 to 50%. Infection with HIV ranged from 0 to 2.6% in limited sexually transmitted disease clinic surveys of heterosexual men and women without a history of IV drug abuse or known sexual contact with persons at increased risk. The modes of HIV transmission are now well understood, but a large amount of biologic variability in efficiency of transmission remains to be explained. The period between initial infection with HIV and the development of AIDS is variable, but the risk for disease progression increases with duration of infection.

HIV risk-related sex behaviors among injection drug users, crack smokers, and injection drug users who smoke crack.

“…[3][4][5][6][7][8] While high risk injection behavior by drug users has dominated the attention of researchers, the sexual transmission of HIV among drug users has received considerably less attention. The importance of sexual transmission is underscored by the fact that injection drug users constitute the leading source for heterosexual and perinatal transmission of HIV to noninjection drug users in the United States.9-'5 Furthermore, male injection drug users typically report more noninjecting sex partners than injecting partners, while female injection drug users are more likely to report that the majority oftheir sex partners are other injectors.…”

Effects of treatment and prevalence-dependent recruitment on the dynamics of a fatal disease

“…Drastic changes in behavior have been observed in some homosexuallyactive populations as a result of the effects of the AIDS epidemic in these communities (see Baldwin and Baldwin 1988, Curran et al 1988, Fineberg 1988, Evans et al 1989, Martin 1987, Saltzman et al 1987, Shechter et al 1988, van Griensven et al 1989a,b, Wilkenstein 1988, McKusick et al 1985, Shilts 1987, and Wiktor et al 1990). The effects of these documented changes in behavior on HIV incidence, and the development of partially-effective drug treatments such as AZT, makes it even more difficult to forecast the timing and magnitude of this epidemic.…”

Age-Structured Core Group Model and its Impact on STD Dynamics

“…Important changes in behavior were observed and documented in various homosexually-active populations including those living in San Francisco, New York and Boston. These observed changes included a reduction in average sexual activity, a decline in risky behavior, and a decrease in the rate of unprotected sexual contacts (see Baldwin and Baldwin 1988, Curran et al 1988, Fineberg 1988, Evans et al 1989, Martin 1987, Saltzman et al 1987, Shechter et al 1988, van Griensven et al 1989a,b, Wilkenstein 1988, and Wiktor et al 1990. Recent data (see below) seem to support the view that at best these changes were not as prevalent as one would have liked to and at worst they may have been kept only for a short period of time.…”