Diagnosis of HIV is normally done by

Options

A. PCR
B. Southern Blot
C. ELISA
D. Auto radiography

Answer

### Step-by-Step Solution:

1. **Understanding HIV**:
- HIV stands for Human Immunodeficiency Virus, which is a virus that attacks the immune system, specifically the CD4 cells (T cells).

2. **Diagnosis of HIV**:
- The diagnosis of HIV is crucial for managing and treating the infection.

3. **Initial Testing Method**:
- The primary test used for diagnosing HIV is the **Enzyme-Linked Immunosorbent Assay (ELISA)**. This test detects antibodies against HIV in the blood.

4. **Interpreting ELISA Results**:
- If the ELISA test result is positive, it indicates that the person may be infected with HIV. However, this result is not definitive.

5. **Confirmatory Testing**:
- To confirm the diagnosis, a second test called **Western Blotting** is performed. This test is used to confirm the presence of HIV antibodies.

6. **Other Testing Methods**:
- Other methods such as PCR (Polymerase Chain Reaction) and Southern Blotting are not typically used for initial HIV diagnosis. PCR is used to detect viral RNA, while Southern Blotting is used for detecting specific DNA sequences.

7. **Conclusion**:
- Therefore, the correct answer to the question is that the diagnosis of HIV is normally done by **ELISA**, followed by confirmatory testing with **Western Blotting** if the initial test is positive.