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Causes of HIV and AIDS

Once the HIV virus enters the body, it seeks out a type of white blood cells called helper T-lymphocytes. These usually defend the body against infection. The virus takes over the T-lymphocyte, causing it to die and releasing billions of copies of the virus back into the blood. These new viruses attach themselves to new T-lymphocytes and so the infection spreads.

For a while, the body manages to keep producing enough T-lymphocytes to keep the immune system working properly. This is sometimes called the "latent phase". But, after some time (usually several years, sometimes as long as fifteen) and without effective treatment, the body reaches a stage where it cannot keep up with the HIV.

Then, the immune system starts to fail and the person starts to become susceptible to other infections which would not normally make them ill. The person is now said to have AIDS.

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