AIDS (Acquired Immune Deficiency Syndrome) is the final stage of a lethal infectious disease, beginning with an infection caused by a virus and progressing to a serious and severe damage to the body's immune system. Infection occurs when the virus integrates with the genetic material of a CD4 white blood cell in the immune system. AIDS was first reported on June 5, 1981, in the United States.

The Human Immunodeficiency Virus (HIV), which is the cause of AIDS, attacks key cells in the human immune system and destroys them. This leaves the body exposed to life-threatening infections, specific cancers, and other illnesses. HIV is a latent virus. People infected by it may have no symptoms for many years, while their immune system weakens until they develop AIDS. The first pediatric AIDS cases were reported in San Francisco in 1982.

A laboratory test counting less than 200/ml CD4 white blood cells is the method used by the U.S. Centers for Disease Control to define AIDS. HIV/AIDS is now a chronic and treatable, but not yet curable, disease. Almost all people infected with HIV will progress to AIDS.

Persons who are carriers of HIV may transmit the virus to others, even in the symptom-free period. However, HIV does not spread as easily as many other pathogens (such as those causing tuberculosis or influenza). The virus can be transmitted from an infected individual to others only through four bodily fluids: blood, semen, breast milk, and vaginal secretions. Worldwide, women are infected more frequently than men.

Transmission of HIV is possible when:

Having unprotected anal, vaginal or oral sexual contact with an infected individual. Sexual intercourse is the most common route for HIV transmission from an infected to a noninfected person; 50 percent of cases are youths between fifteen and twenty-four years old.

Through transfusions of blood and blood products (now extremely rare in the United States and other developed countries), needle sharing (e.g., drug use, medical care in developing countries, piercing or tattooing).

Mother-to-child transmission from a pregnant woman to her fetus, via the placenta, at birth or when breast feeding the infant; the most common cause of HIV infection in young children.

Rare circumstances such as accidental needle or laboratory injuries, artificial insemination or through organ donations.

HIV infection is not spread by air, water or by casual contacts, donating blood or organs (in developed countries where sterilized equipment is used), mosquito bites, or during participation in sports.

HIV/AIDS is a public health, social, developmental, and serious humanitarian crisis in many regions of the world. The total number of people infected by HIV from the start of the epidemic was estimated in 2003 to be 60 million. During 2002 alone eight hundred thousand children younger than 15 years old were infected, at a rate of about two thousand per day.

The most affected region is sub-Saharan AFRICA, followed by Asia, LATIN AMERICA, and EASTERN EUROPE. By the year 2010 it is expected that 20 million of the 42 million ORPHANS in Africa will have lost one or both parents due to AIDS. AIDS has led to a dramatic decline in life expectancy in Africa.

Complex biological, psychological, and sociological factors put young people at greater risk for HIV infection. As a result, efforts to prevent infections are focused on this population, with distinctions between in-school, out-of-school and high-risk youth. Curricula, multimedia initiatives, mass media campaigns, games, and role modeling are just a few of the strategies to promote knowledge and skills for HIV/AIDS prevention worldwide. The key prevention messages focus on eliminating or reducing risks for infection by practicing safe behaviors:

Abstaining from sexual intercourse. (Abstinence is the only way to fully prevent sexual transmission of HIV.)

Reducing the number of sexual partners, delaying the initiation of penetrative sex, and correctly using a condom for intercourse in every case where the HIV status of one of the individuals is unknown reduces the risk of infection.

Avoiding any injection of drugs.

Using one-time, nonshared, sterile needle and syringe for injection of medications, blood transfusions or drugs.

For mothers who are HIV-positive, avoiding breast-feeding their infants.

Avoiding direct contact with blood where the HIV status of the bleeding individual is unknown.

Undergoing an HIV test, to determine one's and one's partners' HIV status.

Mother-to-child infection is preventable in most cases by administering medications to the mother before birth and to the infant after birth.

Children with AIDS were able to mobilize enormous public support and attention since the first days of the epidemic. For example, Ryan White (1971-1990) was a hero in his determination to fight both AIDS and AIDS-related discrimination at school. A federal legislation in the United States that addresses the unmet health needs of persons living with HIV was named after him. Nkosi Johnson (1989-2001), South Africa's longest surviving child born with HIV, captured the hearts of thousands when he spoke of his experiences with HIV/AIDS. Ariel and Jake Glaser and their mother, Elizabeth, all infected with HIV, gave rise in 1988 to the Pediatric AIDS Foundation in the United States.

The UN General Assembly Session on HIV/AIDS decided in June 2001 to ensure a massive reduction in HIV's prevalence and a dramatic increase in access of youth education and youth-specific services necessary to reduce their vulnerability to HIV infection globally by 2010.

See also: Contagious Diseases; Epidemics.


Mann, J., D. Tarantola, and T. Netter. 1992. AIDS in the World. Cambridge, MA: Harvard University Press.

Schenker, Inon. 2001. "New Challenges for School AIDS Education within an Evolving HIV Pandemic." Prospects 31, no 3: 415-434.

Schenker, Inon, G. Sabar-Friedman, and S. S. Sy. 1996. AIDS Education–Interventions in Multi-Cultural Societies. New York: Plenum Press.

World Bank. 2002. Education and HIV/AIDS: A Window of Hope. Washington, DC: World Bank.


Centers for Disease Control. "Division of HIV/AIDS Prevention." Available from

Elizabeth Glaser Pediatric AIDS Foundation. Available from

Joint United Nations Program on HIV/AIDS. Available from

The Body. "An AIDS and HIV Information Resource." Available from