At which stage of HIV infection does one usually show symptoms of AIDS

Options

A. When the infecting retrovirus enter host cells
B. When viral DNA is produced by reverse transcriptase
C. When HIV replicates rapidly in helper T-lymphocytes and damages large number of these
D. Within 15 days of sexual contact with an infected person

Answer

**Step-by-Step Solution:**

1. **Understanding HIV and AIDS**:
- HIV stands for Human Immunodeficiency Virus, which is responsible for causing the disease known as AIDS (Acquired Immunodeficiency Syndrome).
- AIDS is characterized by a significant impairment of the immune system, particularly affecting the cell-mediated immune response.

2. **Mechanism of HIV Infection**:
- HIV primarily targets helper T cells (CD4+ T cells), which play a crucial role in the immune response by stimulating the production of antibodies through B cells.
- As the virus infects and replicates within these T cells, it leads to a reduction in their numbers, compromising the body's ability to fight infections.

3. **Stages of HIV Infection**:
- The infection progresses through several stages, including acute HIV infection, clinical latency, and AIDS.
- Symptoms of AIDS typically appear when the immune system is severely weakened, which is marked by a significant decline in CD4+ T cell counts.

4. **Symptoms of AIDS**:
- Symptoms of AIDS usually manifest when the HIV virus has replicated extensively, damaging a large number of T lymphocytes.
- This stage is characterized by opportunistic infections and various symptoms due to the weakened immune system.

5. **Correct Stage Identification**:
- Among the options provided, the correct stage at which one usually shows symptoms of AIDS is when HIV replicates rapidly in T lymphocytes and damages a large number of cells.

**Final Answer**: Symptoms of AIDS usually appear when HIV replicates rapidly in T lymphocytes and damages a large number of these cells.

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