AIDS stands for Acquired imunodeficiency (or immune deficiency) Syndrome. It results from infection with a virus called HIV, which stands for human immunodeficiency virus. This virus infects key cells in the human body called CD4-positive (CD4+) T cells. These cells are part of the body's immune system, which fights infections and various cancers.
When HIV invades the body's CD4+ T cells, the damaged immune system loses its ability to defend against diseases caused by bacteria, viruses, and other microscopic organisms. A substantial decline in CD4+ T cells also leaves the body vulnerable to certain cancers.
There is no cure for AIDS, but medical treatments can slow down the rate at which HIV weakens the immune system. As with other diseases, early detection offers more options for treatment and preventing complications.
AIDS affects women differently than it does men, and it presents unique issues related to sexuality, childbearing, and side effects of treatments.
What Is The Difference Between HIV And AIDS?
The term AIDS refers to an advanced stage of HIV infection, when the immune system has sustained substantial damage. Not everyone who has HIV infection develops AIDS.
When HIV progresses to AIDS, however, it has proved to be a universally fatal illness. Few people survive five years from the time they are diagnosed with AIDS, although this is increasing with improvements in treatment techniques.
Experts estimate that about half the people with HIV will develop AIDS within 10 years after becoming infected. This time varies greatly from person to person, however, and can depend on many factors, including a person's health status and health-related behaviors.
People are said to have AIDS when they have certain signs or symptoms specified in guidelines formulated by the U.S. Centers for Disease Control and Prevention (CDC).
The CDC's definition of AIDS includes:
All HIV-infected people with fewer than 200 CD4+ T cells per cubic millimeter of blood (compared with CD4+ T cell counts of about 1,000 for healthy people)
People with HIV infection who have at least one of more than two dozen AIDS-associated conditions that are the result of HIV's attack on the immune system
AIDS-associated conditions include:
Opportunistic infections by bacteria, fungi, and viruses. Opportunistic infections are infections that are rarely seen in healthy people but occur when a person's immune system is weakened.
The development of certain cancers (including cervical cancer and lymphomas)
Certain autoimmune disorders Autoimmune disorders are illnesses that result when the immune system attacks an individual's own tissues or cells.
Most AIDS-associated conditions are rarely serious in healthy individuals. In people with AIDS, however, these infections are often severe and sometimes fatal because the immune system is so damaged by HIV that the body cannot fight them off.
The History Of AIDS
The symptoms of AIDS were first recognized in the early 1980s:
In 1981, a rare lung infection called Pneumosystis cariniipneumonia began to appear in homosexual men living in Los Angeles and New York.
At the same time, cases of a rare tumor calledKaposi's sarcoma were also reported in young homosexual men. These tumors had been previously known to affect elderly men, particularly in parts of Africa. New appearances of the tumors were more aggressive in the young men and appeared on parts of the body other than the skin.
Other infections associated with weakened immune defenses were also reported in the early 1980s.
Groups most frequently reporting these infections in the early 1980s were homosexuals, intravenous drug users, and people with hemophilia, a blood disorder that requires frequent transfusions. Blood and sexual transmission were therefore suspected as the sources for the spread of the infections.
In 1984, the responsible virus was identified and given a name. In 1986, it was renamed the human immunodeficiency virus (HIV).
Need To Know:
Because many of the first cases of AIDS in the United States occurred in homosexual men and intravenous drug users, some people mistakenly believe that other groups of people are not at risk for HIV infection. However, anyone is capable of becoming HIV-infected, regardless of gender, age, or sexual orientation.
Facts About AIDS
As of the year 2000, nearly one million people in the U.S. were confirmed to be HIV-positive.
The Centers for Disease Control and Prevention reports that 2.2 million Americans now carry the HIV virus but do not yet have symptoms.
About one out of every three people with HIV infection in the U.S. is a woman.
AIDS is a leading cause of death for American men and women between the ages of 25 and 44.
Since 1992, AIDS has been the fourth leading cause of death among U.S. women between the ages of 25 and 44.
Through June 2000, 438,795 people in the U.S. had died from AIDS (374,422 men and 64,373 women).
By the end of 2000, 36.1 million people worldwide were living with HIV/AIDS, with the vast majority living in developing countries.
Through 2000, 21.8 million people worldwide have died from AIDS.
Between 1991 and 1996, there were more new cases of AIDS among people older than 50 than those between ages 13 and 49. Today, 11% of all new cases of AIDS in the U.S. are now in people over the age of 50.
The HIV carrier rate in the U.S. is now 1 carrier for every 100 to 200 people.
Teenage and young adult women currently make up half of all new HIV infections reported in people 13 to 24 years old.