CD4 Count & Viral Load
HIV infects a particular part of your immune system known as CD4 cells. The HIV virus uses the CD4 cell to make more HIV and in the process the CD4 cells are destroyed. In time the immune system becomes weak and it is unable to fight off infections.
A CD4 count is a measurement of the concentration of CD4 cells in your blood, a normal CD4 count is between 600 and 1,500 in a cubic millimetre of blood (a drop).
A CD4 count below 350, indicates a weakened immune system. This is the time when anti-HIV drug treatment is needed.
If a CD4 count drops below 200, the patient is vulnerable to serious infections.
Therefore the higher the CD4 count the less your immune system has been damaged by HIV.
Viral load is the amount of HIV in the blood. It estimates the number of HIV particles circulating in the blood.
E.g. A viral load of 20,000 would be described as 20,000 copies/ml.
Therefore the higher your viral load, the more HIV you have in your blood.