AIDS and HIV
Acquired Immunodeficiency Syndrome, or AIDS, is the final, life-threatening stage of infection with any of the Human Immunodeficiency Viruses (HIV-1, its many subtypes, or HIV-2), a condition in humans in which the immune system begins to fail, leading to life-threatening infections. HIV is transmitted from person to person sexually (including through anal, oral, and vaginal intercourse, both heterosexually and homosexually), through contact with blood (mainly through equipment used to inject illicit drugs and, rarely, through medical uses of blood), and perinatally (from mother to fetus or newborn during pregnancy, labor, and delivery, or after birth through breast-feeding).
Epidemiology
HIV-1 has spread worldwide, infecting more than 36 million people by 2001. HIV-2, which seems to be less clinically severe and possibly less transmissible from person to person, has mainly been a public health problem for West African nations. Originally epidemic in African and urban settings, HIV and AIDS are now among the most common serious infections globally, including in the Americas and Eurasia and in rural settings. All ages, racial and ethnic groups, and persons of all sexual orientations have been infected.
Symptoms, Diagnosis, and Treatment
Persons initially infected with HIV may develop an "acute retroviral syndrome" characterized by fever, lymph node enlargement, and flu-like symptoms. If symptoms are present, they clear spontaneously, but all infected persons, both with and without symptoms, remain infected and infectious to others indefinitely. The incubation period (the period of time required for the development of symptoms of a disease after infection) is highly variable, averaging about a decade, but ranging from a few months or years to possibly longer than two decades. When sufficient damage to the immune system has been sustained, measured either by laboratory cell counts of the helperT cells or by onset of opportunistic infections, the patient is said to have AIDS. Common manifestations of HIV infection include tiredness, lymph node enlargement, fever, weight loss, and yeast infections of the mouth and vagina.
HIV infection is diagnosed by laboratory detection of evidence of infection, usually identification of HIV-specific antibodies in a blood, oral fluid, or urine specimen. AIDS can be diagnosed in HIV-infected persons in several ways, based on either laboratory evidence of immunodeficiency (lowered levels of CD4+ cells), or clinically by onset of any one or more of a specific list of opportunistic diseases. Opportunistic diseases are those that occur only, or most severely, in patients whose immune systems are impaired. The most common opportunistic diseases in AIDS patients are Pneumocystis carinii pneumonia, Kaposi's sarcoma, toxoplasmosis of the brain, tuberculosis and other mycobacterial infections, and severe herpes, cytomegalo virus, and yeast infections.
As of 2001, all of the more than seventeen antiviral drugs used to treat HIV infection act by interfering with one of the enzymes that HIV needs to complete its life cycle. No treatments result in a cure for HIV infection. The antiviral drugs prevent HIV from growing and further damaging the host's immune system. Thus, the goal of treatment is to preserve the patient's health. Patients must take several antiviral drugs daily. Research on more and better antiviral drugs, and on methods to reconstitute the impaired immune system, is ongoing. A key part of treatment is the prevention of opportunistic infections with specific vaccines and antibiotics.
Prevention
Prevention of HIV infections is deceptively simple: Refrain from having sexual contact and from sharing drug-injecting paraphernalia with anyone who is infected. If you are sexually active, be faithful to one uninfected partner for the rest of your life. However, the rapid and continuing global spread of HIV, despite its well-known and severe clinical consequences, points out how difficult it is to change risky sexual and drug-taking behaviors. Many successful educational and social interventions have been demonstrated, but sustaining them in large populations for long periods requires extensive resources and a strong public health commitment.
(If you have already had sexual activity of any kind, then it is wise to see a health care professional and get checked out immediately. Our centers offer low cost STI/STD testing (only $26!). To contact us and make an appointment today, click here.)
Condoms, even when used correctly and 100 percent of the time during sexual activity, are ultimately an unreliable prevention against the transmission of HIV. The most recent and best studies show that condoms only provide protection against the HIV virus during vaginal intercourse 85 percent of the time. With anal intercourse, the condom prevention rate drops to only about 50 percent. To date, there is no evidence showing condoms offer any prevention when used during oral sex.
The research effort to develop a vaccine to prevent HIV infection has been intense, but the biologic obstacles to success are immense and unprecedented. Because HIV permanently infects cells of the immune system, infection of a single cell results in lifelong infection for the host. Thus, a completely effective vaccine would need to prevent even a single cell from becoming infected. No such vaccine exists for any infection, so HIV will require a new vaccine paradigm. Possible lines of research include stimulating the immune system to detect and eliminate HIV-infected cells, or genetically transforming the HIV in an infected person so as to render it nonvirulent.
Further information on HIV and AIDS is widely available in many user-friendly and scholarly formats. The Internet is a rich source of information, with sites sponsored by public health agencies, such as the Joint United Nations Programme on HIV/AIDS (http://www.unaids.org) and the Centers for Disease Control and Prevention (http://www.cdc.gov), which are particularly recommended. Several texts, popular books, and scholarly journals have been devoted exclusively to AIDS public health issues and scientific research. The first of December has been designated World AIDS Day, and many governments, schools, and organizations sponsor community and educational events to coincide with that date each year.1
Bibliography
Feldman, E. A., and Bayer, R. (1999). Blood Feuds: AIDS, Blood, and the Politics of Medical Disaster. New York: Oxford University Press.
Garrett, L. (1994). The Coming Plague: Newly Emerging Diseases in a World Out of Balance. New York: Farrar, Straus and Giroux.
Mann, J. M.; Tarantola, D.; and the Global AIDS Policy Coalition, eds. (1998). AIDS in the World II/Global Dimensions, Social Roots, and Responses. New York: Oxford University Press.
Shilts, R. (1987). And the Band Played On: Politics, People, and the AIDS Epidemic. New York: St. Martin's Press.
Frequently Asked Questions about HIV/AIDS
Every year, nearly 9 million people under the age of 25 get a new STI (sexually transmitted infection).2 One of these infections is HIV/AIDS. If you've had sex, you could have an STI. Some STIs cause symptoms. Others don't. You could have one and not even know it. Some STIs make you sick today and others can cause problems later in life. These include serious problems like cancer or infertility. Some, such as HIV/AIDS, can even kill you.
- What is HIV/AIDS and how do you get it?
HIV is a virus that invades the immune system and slowly destroys it. This reduces your ability to fight off infections and cancer. Without treatment, people with HIV develop AIDS, which is fatal. You get HIV from having sex with an infected person. Most infected people have no symptoms. But, even without symptoms, they can pass on HIV. You can also get HIV from contact with infected blood. Your risk is greatly increased if you have multiple sex partners or shoot drugs. Babies can get it from their mothers during pregnancy. You can't get HIV from casual contact such as shaking hands or hugging.3 - Am I safe if I only have oral or anal sex?
Anal sex is extremely risky for passing HIV.4 HIV can probably be passed during oral sex.5 - What happens if I'm infected?
At first, you may just have brief flu-like symptoms (tiredness, fever, aches). You may have no other symptoms for years. Even with no symptoms, you can still pass on the disease during sex. If you go on to get AIDS, you may get cancers or multiple infections that other people fight off easily. - How do you treat HIV/AIDS?
If you have HIV, you can prolong your life by taking daily medicine for the rest of your life. However, the drugs are expensive and have significant side effects. If you are pregnant, there are very good drugs to reduce your baby's chance of getting HIV. You should also talk to your doctor about other precautions for your baby. - Am I safe if I always use a condom?
Condoms work much of the time, but ultimately are an unreliable prevention against getting HIV during vaginal sex. If you always use condoms for vaginal sex, you still have a 15 percent chance of getting HIV.6 Therefore, even perfect condom use still leaves you with a significant chance of getting HIV. To date, there is no evidence that condoms reduce your chance of getting HIV during oral sex.7 Even always using condoms for anal sex only offers a prevention against getting HIV 50 percent of the time.8 - What can I do to avoid getting infected?
Don't shoot drugs. Avoid sexual activity if you are single. Be faithful to one uninfected partner for the rest of your life. Already had sex? See a doctor and get checked out.
(If you have already had sexual activity of any kind, then it is wise to see a health care professional and get checked out immediately. Our centers offer low cost STI/STD testing (only $26!). To contact us and make an appointment today, click here.)
1 Adapted from AIDS. Answers.com. Encyclopedia of Public Health, The Gale Group, Inc, 2002. http://www.answers.com/topic/aids, accessed January 22, 2007.
2 H, Berman S, Cates W Jr. Sexually transmitted diseases among American youth: incidence and prevalence estimates, 2000. Perspect Sex Reprod Health. 2004; 36(1): 6-10.
3 Ambroziak J, Levy JA. Epidemiology, natural history and pathogenesis of HIV infection. In: Holmes KK, et al, eds. Sexually Transmitted Diseases. 3rd ed. New York, NY: McGraw Hill. 1999: 251-258.
4 Ibid.
5 Hawkins DA. Oral sex and HIV transmission. Sex Transm Infect. 2001;77(5): 307-308.
6 National Institute of Allergy and Infectious Diseases. Workshop Summary: Scientific Evidence on Condom Effectiveness for Sexually Transmitted Disease (STD) Prevention. Bethesda, MD: National Institute of Allergy and Infectious Diseases; 2001. Available from: http://www.niaid.nih.gov/dmid/stds/condomreport.pdf. Accessed: November 21, 2006; Weller S, Davis K. Condom effectiveness in reducing heterosexual HIV transmission. Cochrane Database Syst Rev. 2002; (1): CD003255.
7 Celentano DD, Sifakis F, Hylton J, Torian LV, Guillin V, Koblin BA. Race/ethnic differences in HIV prevalence and risks among adolescent and young adult men who have sex with men. J Urban Health 2005; 82(4): 610-621.
8 Saracco A, Musicco M, Nicolosi A, et al. Man-to-woman sexual transmission of HIV: longitudinal study of 343 steady partners of infected men. J Acquir Immune Defic Syndr.1993; 6(5): 497-502.