What Is HIV/AIDS?
How Does HIV Harm the Body?
Viruses tend to be specialists. They zero in on a few particular types of cells in the body and move in. The human immunodeficiency virus is best known for targeting the T cells of the immune system. However, it can also attack cells of the brain, nervous system, digestive system, lymphatic system, and other parts of the body.
The immune system is made up of specialized cells in the bloodstream that fight off invading germs to keep the body healthy. The "T" cells (also referred to as "T4," "helper-T," or "CD4" cells) are the brains of the operation. These white blood cells identify invaders and give orders to soldier-type cells, which then battle various bacteria, viruses, cancers, fungi, and parasites that can make a person sick.
Like all viruses, the HIV is only interested in one thing: reproducing itself. Once it has attacked and moved into a T cell, it converts that cell into a miniature virus factory. Eventually there are so many new viruses in the cell that the T cell explodes, scattering the HIV back into the bloodstream. The virus then moves on to fresh T cells and repeats the process. Over time, the HIV can destroy virtually all of an infected person's T cells in this manner.
Then What Happens?
With fewer and fewer "leaders" to rely on for warnings, the "soldier" cells become powerless. They can no longer recognize and fight off common organisms that would not present a problem to a healthy immune system. These organisms may be lying dormant in the body already, or may enter from outside. The immune system's weakness gives them the opportunity to wake up, multiply, and cause illness. Thus, we call these illnesses "opportunistic infections." People with fully functioning immune systems are almost never troubled by these particular infections-but those with damaged immune systems are highly vulnerable to them.
So What's the Connection Between HIV and AIDS?
When a person with an HIV-weakened immune system comes down with one or more of these rare opportunistic infections, or has a T cell count below 200 or 14%, that person may be diagnosed by a doctor as having AIDS. "AIDS" stands for "Acquired Immune Deficiency Syndrome." The "syndrome" part means that AIDS is not a single disease but a collection of diseases. The Centers for Disease Control (CDC) has put together a list of 26 "AIDS-defining illnesses" in adults. (Click here to view the list of CDC AIDS-defining illnesses.) Diagnosis of AIDS in children involves a list of slightly different ailments.
This article was provided by HIV Coalition (HIVCO).