What Do You Know About HIV/AIDS?

Around this time, doctors in Los Angeles and New York were reporting rare cases of pneumonia, cancer, and other illnesses among male patients who had sex with other men. These conditions were not normally found in people with healthy immune systems. It was many years before scientists developed a test for the virus.

A blood test is the only way to know for sure if you have HIV infection. Symptoms are not always reliable. They can be mistaken for other illnesses. Severe symptoms like rapid weight loss or chronic infections usually do not appear for years, if at all. Even if you don’t have any symptoms, you can still infect other people. This is why early testing is so important.

According to the CDC, an HIV-infected person has AIDS when he or she has fewer than 200 CD4 cells. These cells are an important part of the body’s immune system and help to fight off infection. The definition of AIDS also includes developing one or more of 26 medical conditions, including recurrent pneumonia and Kaposi sarcoma (a cancerlike disease affecting the skin), even if that person doesn't meet the CD4+ criteria. Many of these conditions don’t affect healthy people, but someone with AIDS has little or no defense against infection because the immune system is too weak.

When you are exposed to HIV, your immune system makes antibodies (a kind of protein) to fight that specific infection. These antibodies can be measured by a blood test. It usually takes two to eight weeks after infection before HIV antibodies can be detected. For some people, it may take longer, but 97 percent of people will develop antibodies within the first three months after infection. Once the antibodies are detected, a person is considered HIV-positive. A person can also be diagnosed with HIV infection when a blood test detects the actual virus particles.

HIV targets a kind of white blood cell called a CD4 positive T cell, or T4 cell. This type of cell is the immune system's key fighter of infections.

A normal count is 1,000 or more CD4 positive T cells per cubic milliliter.

HIV is found mostly in blood, semen, or vaginal fluid. An HIV-positive person can pass the virus through unprotected sex (oral, vaginal, or anal) and through sharing needles or syringes. Women can pass the virus to their babies before birth, during birth, or through breast-feeding. The risk of getting HIV from a blood transfusion is very low. Since 1985, all donated blood in the U.S. is tested. HIV is not spread through casual contact, such as shaking hands or hugging, or from sharing food, glasses, utensils, towels, bedding, toilet seats, or pets.

The drugs are designed to attack the virus at different stages of its life cycle.

Currently, no vaccine is available for HIV. Protect yourself by abstaining from sex, by using a latex condom when you do have sex, and by avoiding any unprotected sex. Remember, a person can be HIV-positive and have no symptoms. Have yourself tested to learn your status. Oral contraceptives and spermicides don’t protect you from getting HIV.