Final answer:
AIDS infections occur in three stages: acute HIV infection, clinical latency, and AIDS. The stages are characterized by different CD4 T-cell counts and symptoms.
Step-by-step explanation:
The progression of AIDS infections occurs in three stages.
Stage 1: Acute HIV infection. During this stage, patients may experience flu-like symptoms and have more than 500 cells/μL CD4 T cells. They are highly contagious.
Stage 2: Clinical latency. HIV enters a period of dormancy, and patients have between 200 and 499 cells/μL CD4 T cells. The virus is still active but reproduces at low levels, and patients may not experience any symptoms of illness.
Stage 3: Acquired immunodeficiency syndrome (AIDS). Patients are diagnosed with AIDS when their CD4 T-cell count drops below 200 cells/μL or when they develop certain opportunistic illnesses. During this stage, the immune system becomes severely damaged by HIV, and patients develop various symptoms and become highly infectious.