Understanding AIDS/HIV - the Basics

AIDS (acquired immune deficiency syndrome) isn't a disease in itself. Instead, AIDS is a condition that develops when a person's body has been weakened by HIV (the human immunodeficiency virus). HIV is found in blood and sexual fluids and spreads mainly through unprotected sexual contact and the sharing of IV drug needles and equipment.

When a person becomes infected with HIV, it damages the immune system. A "deficient" immune system is unable to protect a person -- a problem called immunodeficiency. The immune system can no longer fight off the many germs and pathogens that a person normally encounters, so a person infected with HIV becomes ill from diseases that don't usually affect someone without HIV.

It can take HIV many years to damage the immune system enough to make the person vulnerable to these diseases, called opportunistic infections (OIs). These infections take the "opportunity" to invade because the immune system cannot fight them off. When doctors see someone with one of these diseases, they know that HIV is probably responsible, and the person may be diagnosed with AIDS.

As HIV slowly invades a specific immune cell -- the CD4 T-cell -- HIV uses the immune cell's genetic material to reproduce itself and then kills the CD4 T-cell.

An HIV-infected person may not have any symptoms of disease during this time -- called the asymptomatic period. This can last 10 years or more for some people. During this time, the person's CD4 T-cell count is watched closely to guide treatment. Once the CD4 T-cell count goes below 200, a person is diagnosed with AIDS. There is no cure for AIDS, but there are now treatments to control it.

The Worldwide HIV/AIDS Pandemic

The first AIDS case was documented in 1981, and HIV has since spread worldwide. Over 22 million people have died worldwide, and the epidemic continues to spread. Sub-Saharan Africa has the greatest number of people who are infected. The World Health Organization (WHO) and the United Nations' UNAIDS office estimate that over 33% of adults are infected with HIV in some areas of Africa. Millions of children have been orphaned. The epidemic is also growing rapidly in Eastern Europe and Asia. Nearly 40 million people worldwide are now living with HIV.

In the United States and the developed world, the use of combination treatments has turned AIDS into a chronic disease. People now live long lives with HIV when they work closely with their health care providers and are committed to their treatment plans. Unfortunately, AIDS medications are expensive and unavailable to the majority of people in the world living with AIDS.

There are growing concerns that some high-risk groups believe they don't have to be worried about HIV anymore. The fact that people now live longer with HIV doesn't change the fact that HIV can infect anyone who exchanges infected blood or sexual fluids with another person.