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38.1.4 Clinical course of HIV infection

It is divided in different phases based on the quantity of virus in the patient's plasma and CD4+ T cell count in the blood.

 

1.  Acute phase

It begins after three to six weeks of infection. Acute phase is characterized by viremia and initial reduction in CD4+ T cell count while the T cell count may gradually return to normal.

2.  Chronic phase

It may last for many years and the virus is held within the lymphoid tissue. Patients do not show any symptoms or may suffer from some minor infection.

3.  Lethal phase

This phase is reached when the blood CD4+ T cell count drops below 200 cells /mm3 . This stage is known as AIDS and is characterized by immunosuppression and opportunistic infections.

 

38.1.5 Elite controllers and long-term nonprogressors

Most of HIV sufferers gradually develop AIDS but approximately 1% of infected population does not develop the disease. These patients so called Elite controllers have persistent viremia and high count of CD4+ and CD8+ T cell but no disease for at least ten to fifteen years. Prevention of AIDS in the elite controllers has been linked to genetics of the individual but the actual factors are yet to come out.