HIV is transmitted in several fashions. These routes of transmission include sexual contact with an infected individual; this is the most common route of transmission. HIV is also transmitted, in rare cases, through being stuck with a needle that has been used by an infected person. Additionally, a baby can contract the disease by being born to an infected mother or by breastfeeding from an infected woman.

HIV is an enveloped human retrovirus. The virion contains two copies of the RNA genome and three key enzymes: protease, integrase, and reverse transcriptase. The inner core of HIV consists of the p24 and p17 Capsid proteins. Clinical diagnosis of HIV infection involves detection of serum antibodies directed against

HIV is thought to have originated from chimpanzees indigenous to Africa. Researchers claim that chimpanzees were the source for HIV-1 and the simian virus (SIVcpz) is almost identical to HIV-1. Chimpanzees are thought to be the reservoirs of HIV but are only rarely infected with SIVcpz. The process where viruses pass from animal to human is called zoonosis. Researchers think that HIV could have crossed species when a human killed a chimpanzee and ate it for food or HIV was transferred iatrogenically (i.e. via medical experiments).

Acquired Immune Deficiency Syndrome (AIDS) is the leading cause of death in persons aged 25-44. It is characterized by a progressive decline in immune function over a period of 8-15 years, which is paralleled by an increase in susceptibility to a wide range of opportunistic infections. Cryptococcis, crytosporidiosis, and pneumocystis carinii pneumonia are a few such infections, which often end the lives of those living with AIDS. Human Immunodeficiency Virus (HIV) is the etiologic agent that causes AIDS. HIV is a member of the retrovirus family of which there are two sub-families: HIV-1 and HIV-2. HIV-1 is more prevalent and more pathogenic than HIV-2. HIV-1 is responsible for infections globally, whereas HIV-2 is found predominantly in countries of West Africa (Stevenson J, AIDS in South America takes center stage, 2000).

Although the current anti-retroviral drug therapy has proven successful at reducing patient viral loads, most HIV infected individuals will never benefit from these therapeutic agents. Ninety percent of all new HIV infections occur in developing countries where adequate financial resources are not available to allow for drug access. Even in wealthy, industrialized nations, where antiviral drugs are available, poor drug tolerance and emerging drug-resistant viral strains make long-term responsiveness to antiviral therapy far from common. Tragically, once patients are removed from drug therapy, their viral loads increase to levels equivalent to those detected prior to treatment. This is likely a result of latent virus reactivation. Successful containment of the AIDS pandemic will ultimately require an effective vaccination strategy designed to prevent HIV infection (Website 3).

The infection process begins when gp120 binds to the principle receptor on the target cell, CD4. This induces conformational changes within the gp120 protein, which exposes a binding site for a co receptor. Many strains of HIV-1 exist, but most fit into one of two categories. HIV strains that efficiently infect T cells are referred to as T-cell tropic and preferentially utilize the chemokine receptor CXCR4 as the co receptor. Other strains of HIV, which efficiently infect cells of the monocyte/macrophage lineage,

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