HIV Virus

HIV (Human Immunodeficiency Virus) is the virus that causes the deadly disease of AIDS. This virus is responsible for gradually destroying the human immune system, and subjecting it to various invincible opportunistic infections. However, having the presence of HIV virus does not mean that the person is simultaneously suffering from AIDS. Intact, AIDS is the final stage of the HIV infection

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About HIV, The Lentivirus

HIV is a lentivirus, belonging to the retrovirus family. Retrovirus is typically responsible for most viral infections in primates. While lentivirus, as the name suggests, is a slow subtype of retrovirus. This subtype takes a long time for incubation, before it gets fully active.

What the HIV Virus does?

HIV destroys the immunity cells in the human body, namely the:

• CD4/T-Cells or the helper T-Cells, reducing its count to below 200
• Macrophages
• Dendritic cell

It destroys these cells by three main ways:

• They increase the rate of apoptosis within the helper T-cells. Apoptosis is a process of mass cell death, by means of blebbing, cell shrinkage, loss of cell membrane, and chromosomal DNA fragmentation.
• It directly kills the infected host cells
• It kills the infected CD4 T-cells, by producing CD8 lymphocytes that can destroy the infected T-cells.

This destructive process of killing the CD4 T-cells and bringing its count down to 200, takes several years. Science has established that a count of CD4 cells below 200 invariably leads to loss of immunity and eventual death, as denoted by the final stage of AIDS.

TYPES of HIV Virus

HIV virus are of two main types

1. HIV 1- This virus is said to have originated from Chimpanzees, and is considered to have a global prevalence. They have a high ability and transmission mechanism.
2. HIV II- These virus have originated from Sooty Mangabey (a primitive species of monkey mainly found in Ghana).

The HIV II Virus is characterized by a confined area of prevalence. HIV II viruses are therefore restricted only within the African continent. They have a comparatively low capacity of transmission, and hence could not reach out to the rest of the world.

These Types of HIV virus again has several Subtypes.

GROUP M subtypes:
A- West Africa
B-Europe,USA,Japan
C-South Africa, Nepal
D-Eastern and Central Africa
E-Not discovered
F-Eastern Europe,South America
G-Central Europe
H-Central Africa
I- it's a combination of several subtypes
J-Caribbean
K-Congo, Cameroon

HIV Structure:

HIV is spherical in shape, with spikes all over its body. Its size is 4 millionth of an inch. It is coated by a viral envelope (a fatty material). The spikes on its surface are made of gp120 and gp41 protein. These spikes cling into the CD4 cells of the host's body, making the viral envelope fuse with it. While, the next layer, below the viral material, also known as matrix is made of p17 protein. Within the core, reside two strands of RNA, which is the genetic material of the HIV virus.

It has a very small number of genetic materials, as compared to other organisms. The nine genetic materials are called rev, tat, nef, vpu,vpr, vif, gag,env and pol. It also consists of enzymes like reverse transcriptase, integrase and protease, required for its cellular multiplication. These enzymes are blended with the enzymes in the CD4 cells, altering the RNA into DNA form, producing HIV proteins and enzymes, in reaction with the other chemical components. This finally leads to the death of the host cells.

The HIV virus is the most complex virus ever encountered by mankind. Many of its mysteries have been unleashed through persistent research and studies. While many, are yet to be revealed. Even at a microscopic level, it keeps reflecting the incompetence of human to defeat this tiny organism.