HIV

The successful introduction and spread of the human immune-deficiency virus (HIV) into the global human population has occurred for many reasons. The discovery and widespread use of penicillin and other

antibiotics meant that there was treatment and cure for most sexually transmitted infections. The existence of these new drugs changed how people perceived risks associated with sexual activity. The development of hormonal contraceptives hastened the pace of change in sexual practices, as prevention of pregnancy without barrier methods became a possibility. Lifestyles were also changing: people were moving into regions that were previously uninhabited by man and long-distance travel became easier and much more common, allowing for greater social migration and sexual mixing. Although the virus may have been first introduced to humans earlier in the 20th century (most likely contracted from infected animals), it was in the 1970s that wider dissemination occurred.
For industrialized countries, the first evidence of the AIDS epidemic was among groups of individuals who shared a common exposure risk. In the United States, sexually active homosexual men were among the first to present with manifestations of HIV disease, followed by recipients of blood or blood products, then injection drug users, and ultimately, children of mothers at risk. Women have represented an increasing proportion of reported AIDS cases in the United States, accounting for 26% of adult cases in 2001 (CDC, 2002). Seventy-eight percent of AIDS cases in women are in African Americans and Hispanics, as compared with 52% of cases in men.
In developing countries, the AIDS epidemic manifested quite differently, both because the signs and symptoms were harder to distinguish from competing causes of morbidity and mortality, and because the epidemic was more generalized, instead of seemingly limited to certain “high-risk” groups. Worldwide, women now represent 50% of all adults living with HIV and AIDS (Table 1-1), and this proportion had been steadily increasing over time (UNAIDS, 2002).
This chapter reviews the epidemiology of HIV/AIDS, beginning with how HIV is transmitted and the variables involved; the natural history of HIV infection in women — both without treatment and in the era of highly active antiretroviral therapy (HAART), and concludes with future issues regarding the HIV/AIDS epidemic