HUMAN IMMUNODEFICIENCY VIRUS (HIV) AND ACQUIRED IMMUNE DEFICIENCY SYNDROME (AIDS)
Although the human immunodeficiency virus (HIV) is a viral infection, there are several factors that set it apart from other STIs and also shed some light on why the acquired immune deficiency syndrome (AIDS) debate has become so politically charged. HIV/AIDS appeared at a time when modern medicine was believed to be well on its way to reducing epidemic disease (D. Altman, 1986). In addition, AIDS was first identified among gay men and, as of 1995, the largest number of cases in this country were gay and bisexual men and intravenous drug users.
Because of this early identification, the disease was linked with “socially marginal” groups in the population (D. Altman, 1986; Kain, 1987). The media gave particular attention to the lifestyle of “victims” and implied that social deviance has a price. One study found that 1 in 5 people believed that people who got AIDS through sex or drugs got what they deserved (Valdiserri, 2002). Although the stigma of HIV/AIDS decreased in the 1990s, in 1999, nearly 1 in 5 American adults said they “fear” a person with AIDS (Herek et al., 2002). We will talk more about public attitudes about AIDS later in this chapter.
AIDS is caused by a viral infection with the human immunodeficiency virus (HIV), a virus primarily transmitted through body fluids, including semen, vaginal fluid, breast milk, and blood. During vaginal or anal intercourse, this virus can enter the body through the rectum, vagina, penis, or mouth. It is also possible to transmit the virus during intravenous drug use by sharing needles. Oral sex may also transmit the virus, although it is difficult to measure the risk associated with oral sex because few people engage exclusively in oral sex. Even so, the research has consistently shown that the risk is lower than that of unprotected vaginal or anal sex (Kohn et al., 2002; E. D. Robinson & Evans, 1999). Kissing has been found to be low-risk for transmitting HIV, especially when there are no cuts in the mouth or on the lips.
Like the herpes virus, HIV never goes away; it remains in the body for the rest of a person’s life. However, unlike the herpes virus, an untreated HIV infection is often fatal. After a person is infected, the virus may remain dormant for awhile and cause no symptoms. This is why some people who are infected may not realize that they are. However, a blood test can be taken to reveal whether or not someone is HIV-positive. Even a person who does not know that he or she has been infected can transmit the virus to other people immediately after infection.
HIV attacks the T-lymphocytes (tee-LIM-foe-sites; T-helper cells) in the blood, leaving fewer of them to fight off infection. When there is a foreign invader in our blood
stream, antibodies develop that are able to recognize the invader and destroy it. However, if the antibodies cannot do this or if there are too many viruses, a person will become ill. These antibodies can be detected in the bloodstream anywhere from 2 weeks to 6 months after infection, which is how the screening test for HIV works. The immune system also releases many white blood cells to help destroy invaders.
HIV attaches itself to the T-helper cells and injects its infectious RNA into the fluid of the helper cell. The RNA contains an enzyme known as reverse transcriptase (transSCRIPT-ace), which is capable of changing the RNA into DNA. The new DNA takes over the T-helper cell and begins to manufacture more HIV (see Figure 15.10).
The attack on the T-helper cells causes the immune system to be less effective in its ability to fight disease, and so many opportunistic diseases infect people with AIDS that a healthy person could easily fight off (we will discuss these diseases later in this chapter). No one knows exactly why some people acquire the virus from one sexual encounter whereas others may not be infected even after repeated exposure. It appears that a person is more at risk for acquiring HIV who already has another STI (Gilson & Mindel, 2001; Hader et al., 2001).
It is unknown where exactly HIV came from, although scientists have many different theories. None of these theories has been proven, however. In the early 1980s, a number of gay men, mostly in Los Angeles and New York City, began coming down with rare forms of pneumonia and skin cancer. Physicians began calling the disease GRID, for
“gay-related immunodeficiency syndrome.” It was hypothesized that there was a new infectious agent causing the disease, that the immune system was being suppressed by a drug that the infected persons were using, or that perhaps a sexual lubricant was involved. Many physicians felt that this infectious agent would quickly be isolated and wiped out. Today, it is anticipated that the AIDS virus will continue to infect people for the next several decades without a cure.