HIV and AIDS: Who is at risk, what precautions are needed

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Although the worldwide media has been covering the ravages of AIDS for more than a decade, the disease still inspires tremendous fear in people who know little about it.

HIV stands for Human Immunodeficiency Virus. The virus attacks a person's immune system — the system that defends the body from illness. The average time between infection and the development of AIDS is 10 years or more. The virus can be spread to other people from the time of infection onward.

AIDS stands for Acquired Immune Deficiency Syndrome, which a person develops when the immune system becomes so damaged it can no longer fight off infections. Official AIDS diagnosis is made when a person's T-cell count is below 200 or he or she develops an opportunistic infection.

HIV is spread most commonly through unprotected sex (i.e., without a latex condom) with an HIV-positive partner: through blood-to-blood contact, most often by sharing needles with an HIV-positive individual; via congenital transfer, i.e., from an infected mother to her baby during pregnancy, childbirth or breast-feeding — although the latter situation is rare. Before 1985, many people were inadvertently infected through blood transfusions. Such infections are now rare, estimated at one in 225,000 by the American Red Cross. Donors cannot contract HIV by giving blood.

HIV-AIDS is not spread through casual contact. You cannot contract the virus through sitting beside a person who has HIV-AIDS, being in the same room with such a person, nor through sharing eating utensils or drinking glasses; through touching, shaking hands, hugging or kissing a person with HIV or AIDS; using the same restrooms, phones, towels, bedding and/or drinking fountains as someone with HIV-AIDS.

Insect bites cannot transmit the disease, nor can someone's tears.

The ELISA blood test is used on all blood donated within the United States. This test is used to detect HIV antibodies. Anyone testing positive should undergo the "Western Blot" test. However, there is a window of 6 to 12 weeks. An HIV test indicates if someone has been infected three months or longer.

Anyone can get AIDS, though high-risk groups include intravenous drug users and those engaging in unsafe sex with an infected partner or with more than one person.