Which of the following diseases is caused by virus and transmitted by mosquito?

Options

A. Typhus
B. Yellow fever
C. Plague
D. Filariasis

Answer

To determine which of the diseases listed is caused by a virus and transmitted by mosquitoes, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Diseases**: The options given are typhus, yellow fever, plague, and filariasis.

2. **Classify Each Disease**:
- **Typhus**: This is a bacterial disease caused by Rickettsia bacteria and is not transmitted by mosquitoes.
- **Yellow Fever**: This is a viral disease caused by the yellow fever virus and is transmitted by mosquitoes, specifically the Aedes aegypti mosquito.
- **Plague**: This is also a bacterial disease caused by Yersinia pestis and is not transmitted by mosquitoes.
- **Filariasis**: This is a parasitic disease caused by filarial worms, and while it is transmitted by mosquitoes, it is not a viral disease.

3. **Determine the Correct Answer**: Since we are looking for a disease that is both viral and transmitted by mosquitoes, the correct answer is **yellow fever**.

### Final Answer:
The disease caused by a virus and transmitted by mosquitoes is **yellow fever**.

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