AIDS - acquired immunodeficiency syndrome - was first reported in the United States in 1981 and has since become a major worldwide epidemic. When the first AIDS cases were recognized, few would have thought that so many years would pass without a cure being discovered. There still remains speculation as to the causative agent; although the controversy continues, AIDS is commonly thought to be caused by the human immunodeficiency virus (HIV). By killing or damaging cells of the body's immune system, HIV progressively destroys the body's ability to fight infections and certain cancers. By 2001, more than 750,000 cases of AIDS had been reported in the United States and as many as 1,000,000 Americans were thought to be infected with HIV - an invection rate of about 0.4%. Growing most rapidly among minority populations, it is a leading killer of African-American males. The rates of infection are very high in some southern African countries, with the situation in Botswana being described as shocking - by 2001 some 36% of the adult population was infected. South Africa came second in that region with a 20% rate.

HIV is spread most commonly by having unprotected sex with an infected partner, contact with infected blood or being born to an HIV infected mother. Approximately one-quarter to one-third of all untreated pregnant women infected with HIV will pass the infection to their babies. HIV also can also be spread to babies through the breast milk of infected mothers.

Studies of families of HIV-infected people have shown clearly that HIV is not spread through casual contact such as the sharing of food utensils, towels and bedding, swimming pools, telephones, or toilet seats. HIV is not spread by biting insects such as mosquitoes or bedbugs. Scientists also have found no evidence that HIV is spread through sweat, tears, urine, or feces.

Symptoms
Many people do not have any symptoms when they first become infected with HIV. Some people, however, have a flu-like illness within a month or two of being exposed to the virus. This illness may include fever, headache, tiredness or enlarged lymph nodes. These symptoms are often mistaken for those of another viral infection. During this period, people are very infectious and HIV is present in large quantities in genital fluids.

More persistent or severe symptoms may not surface for years after infection in adults, or for two years in children born with HIV infection. This period of "asymptomatic" infection is highly individual. Some people may begin to have symptoms within a few months, while others may be symptom-free for more than 10 years.

Even during the asymptomatic period, the virus is multiplying, infecting, and killing cells of the immune system, especially T4 cells (CD4+). At the beginning of its life in the human body, the virus disables or destroys these cells without causing symptoms.

The term AIDS applies to the most advanced stages of HIV infection. The Center for Disease Control defines AIDS as all HIV-infected people who have fewer than 200 T4 cells per cubic millimeter of blood. Healthy adults usually have 1,000 or more. In addition, the definition includes over 20 clinical conditions that affect people with advanced HIV disease. Most of these conditions are opportunistic infections that generally do not affect healthy people. Amongst people with AIDS, these infections are often severe and sometimes fatal because the immune system is so damaged by the virus that it can no longer fully resist.

Children with AIDS may get the same opportunistic infections as adults. In addition, they also have severe forms of the bacterial infections that all children may get, such as conjunctivitis (pink eye), ear infections or tonsillitis.

During the course of HIV infection, most people experience a gradual decline in the number of T4 cells, although some may have abrupt and dramatic drops in their T4 cell counts. A person with a T4 cell count above 200 may experience some of the early symptoms of HIV disease, while others may have no symptoms even though their T4 cell count is below 200.

Diagnosis
Because early HIV infection often causes no symptoms, a doctor usually diagnoses it by testing a person's blood for the presence of antibodies to HIV. HIV antibodies generally do not reach detectable levels in the blood for one to three months following infection.

People exposed to the virus should get an HIV test as soon as they are likely to develop antibodies to the virus i.e. within 6 weeks to 12 months after possible exposure to the virus. By detecting it early, people with HIV infection can discuss with their doctor when they should start treatment to help their immune systems combat HIV and help prevent the emergence of opportunistic infections. Early testing also alerts HIV-infected people to avoid high-risk behaviors that could spread the virus to others.

Health care providers diagnose HIV infection by using two different types of antibody tests, ELISA and Western Blot. If a person is highly likely to be infected with HIV and yet both tests are negative, the doctor may request additional tests. The person also may be told to repeat antibody testing at a later date, when antibodies to HIV are more likely to have developed.

Polymerase chain reaction (PCR) testing is more expensive and labor-intensive but can detect the virus even in someone only recently infected. Urine testing for HIV antibodies is not as sensitive or specific as blood testing but may be used for someone who does not want blood drawn.

Babies born to mothers infected with HIV may or may not be infected with the virus, but all carry their mothers' antibodies to HIV for several months. If these babies lack symptoms, a doctor cannot make a definitive diagnosis of HIV infection using standard antibody tests until after 15 months of age. By then, babies are unlikely to still carry their mothers' antibodies and will have produced their own, if they are infected. Health care experts are using new technologies to detect HIV itself to more accurately determine HIV infection in infants between ages 3 months.

To effectively deal with the confusion about AIDS, the diagnosis and it's treatment requires personal involvement. It really is important that everyone facing AIDS must educate themselves carefully in order to be prepared for the challenges and comfortable with the decisions that will need to be made. While many alternative therapies have turned out to be less effective than initially thought, there is much that can be done to enhance immune function and keep the infection in check.

Conventional Treatment
Three main classes of antiviral drugs are used to treat HIV infection: nucleoside analog reverse transcriptase inhibitors (e.g., zidovudine [ZDV, AZT, Retrovir], didanosine [ddI, Videx], zalcitibine [ddC, Hivid], stavudine [d4T, Zerit], lamivudine [3TC, Epivir]); non-nucleoside reverse transcriptase inhibitors (e.g., nevirapine [Viramune], delavirdine [Rescriptor]); and protease inhibitors (e.g., saquinavir [Fortovase, Invirase], ritonavir [Norvir], indinavir [Crixivan], nelfinavir [Viracept]). Several other investigational drugs are also used. Treatment with two to four of these drugs is standard. Treatment of the complications of AIDS is specific to the infection or complication present, and frequently includes antibiotics, antifungal medications, corticosteroids, and heart drugs.