Which one is not spread by droplet infection?

Options

A. Tuberculosis
B. Diphtheria
C. Pertussis
D. Gonorrhoea

Answer

To determine which disease is not spread by droplet infection, we will analyze each option provided in the question.

### Step-by-Step Solution:

1. **Identify the Diseases**: The options given are:
- Tuberculosis
- Diphtheria
- Pertussis (Whooping Cough)
- Gonorrhea

2. **Analyze Tuberculosis**:
- **Cause**: Tuberculosis is caused by *Mycobacterium tuberculosis*.
- **Transmission**: It spreads through respiratory droplets when an infected person coughs or sneezes.
- **Conclusion**: Tuberculosis is spread by droplet infection.

3. **Analyze Diphtheria**:
- **Cause**: Diphtheria is caused by *Corynebacterium diphtheriae*.
- **Transmission**: Similar to tuberculosis, it spreads through respiratory droplets.
- **Conclusion**: Diphtheria is also spread by droplet infection.

4. **Analyze Pertussis (Whooping Cough)**:
- **Cause**: Pertussis is caused by *Bordetella pertussis*.
- **Transmission**: This disease is also transmitted through respiratory droplets.
- **Conclusion**: Pertussis is spread by droplet infection.

5. **Analyze Gonorrhea**:
- **Cause**: Gonorrhea is caused by *Neisseria gonorrhoeae*.
- **Transmission**: Unlike the previous diseases, gonorrhea is primarily spread through sexual contact, not respiratory droplets.
- **Conclusion**: Gonorrhea is **not** spread by droplet infection.

6. **Final Answer**: Based on the analysis, the disease that is not spread by droplet infection is **Gonorrhea** (Option 4).