AIDS and HIV Infection • Facts
The basic facts about AIDS, HIV and HIV+
AIDS stands for acquired immunodeficiency syndrome, a pattern of devastating infections caused by the human immunodeficiency virus, or HIV, which attacks and destroys certain white blood cells, that are essential to the body's immune system.
When HIV infects a cell, it combines with that cell's
genetic material and may lie
inactive for years. Most people infected with HIV are still healthy and can live for
years with no symptoms or only minor illnesses. They are infected with HIV,
but they do not have AIDS.
(HIV+ is a synonym for HIV positive.)
After a variable period of time, the virus becomes activated and then leads progressively to the serious infections and other conditions that characterize AIDS. Although there are treatments that can extend life, AIDS is in fact a fatal disease. Research continues on possible vaccines and, ultimately, a cure. For the moment, however, prevention of transmission remains the only method of control.
The facts: route of the HIV infection in adults
HIV targets two groups of white blood cells called CD4+ lymphocytes and monocytes/macrophages. Normally, CD4+ cells and macrophages help recognize and destroy bacteria, viruses or other infectious agents that invade a cell and cause disease.
In an HIV-infected person, the CD4+ lymphocytes are killed by the virus, while the macrophages act as reservoirs, carrying HIV to a number of vital organs.
HIV attaches itself to the CD4+ lymphocyte and makes its way inside. This causes the cell to produce more HIV but, in doing so, the cell is destroyed. As the body's CD4+ cells are depleted, the immune system weakens and is less able to fight off viral and bacterial infections.
In fact is that in general, about 50 percent of HIV-infected adults are likely to develop AIDS within 10 years after first becoming infected.
The good news is that early AIDS-preventive treatment with improved drugs is significantly prolonging life for persons with AIDS.
HIV+ people and "opportunistic" infections
The infected person becomes susceptible to a wide range of "opportunistic" infections; such as Pneumocystis carinii pneumonia, which rarely occurs in persons with normal immune systems.
Tuberculosis (TB) poses a particular threat to HIV+ (HIV-positive) people, especially in areas of the world where both TB and HIV infection are increasing at alarming rates. Millions of TB carriers who would otherwise have escaped active tuberculosis are now developing the disease because their immune systems are under attack from HIV. TB also progresses faster in HIV-infected persons, and is more likely to be fatal if undiagnosed or untreated. In fact, TB is now the leading killer of HIV-infected Africans.
HIV+ people and cancer
HIV-infected persons are also more susceptible to otherwise rare cancers such as Kaposi's sarcoma, a tumor of the blood vessels or the lymphatic vessels.
HIV may also attack the brain, causing neurological and neuro-psychiatric problems.
The facts: route of the HIV infection in infants and children
Most HIV-infected infants and children acquired the infection from their mothers before or during birth, and after birth during breastfeeding. In fact, only a small proportion is infected through HIV-contaminated blood transfusions or injections.
AIDS disease progression in HIV+ newborns
There are two patterns of disease progression in children infected from birth. About half these children progress rapidly to AIDS, but others remain symptom free for years, as adults do. Studies show that, in developed countries, approximately two-thirds of infected children are still alive at age 5 years. In developing countries, the figure of alive HIV+ childern ranges between 30 and 65 percent.