by Vijaya

Created on: January 15, 2007   Last Updated: December 08, 2009

The irony is not lost on us. We live in a world where our ideals grow larger, our scientific progress expands everyday, and our understanding of how things work around us is more than ample.

And yet, when something so small becomes one of the most widespread killers of the 21st century, our ability to find a solution is replaced with, quite simply, inability. No, the irony is not lost.

Today, an estimated 33.4 - 43.0 million people live with HIV and AIDS. Since its discovery in 1981, it has killed 25 million. Facts, figures - although moving - will mean nothing to us without knowing what exactly this pandemic does. This, perhaps, may help us realise the true extent of what we face.

HIV stands for Human Immunodeficiency Virus which will, eventually lead to AIDS if not treated. HIV is a retrovirus: like all viruses, it needs a host - i.e. an organism - to survive and to reproduce. It has adapted to infecting and using the cells of our immune system. However, a retrovirus is different.

Before its discovery, we believed all organisms used the same system to make their genetic code into the proteins they needed. The flow of the information was all one way- DNA to RNA to proteins. Retroviruses carry their genetics as RNA, but instead of using its host's system to convert its RNA into DNA, it produces its own enzyme, called reverse transcriptase, to carry out and catalyse the conversion.

When HIV enters the bloodstream of an organism, a protein on its surface - gp120 - is attracted to receptors called CD4 on CD4+ cells. CD4+ helps the immune system to function properly - the receptors pick up antigens, which are dangerous to us - and help to create antibodies that destroy them. When the protein on the HIV virus and the receptors meet, a reaction makes the HIV bind itself to the cell. Then, it fuses itself to the cell membrane in order to enter.

Once the virus is joined, it releases three things into the cell: the RNA, the enzyme reverse transcriptase and another enzyme called integrase. The reverse transcriptase then builds the DNA strands from the RNA; the DNA is called a provirus. The DNA that is created then goes toward the nucleus, where the cells' genetic code is housed. The enzyme integrase helps the viral DNA get into the cells' own DNA.

However, even though the cell is now infected, the virus can remain dormant for many years. Many people can have HIV and never have it develop into AIDS. Approximately 50,000 people in the UK have HIV without knowing it; that's

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