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

Options

A. Typhus
B. Rocky mountain fever
C. Yellow fever
D. Filariasis

Answer

To solve the question "Which of the following diseases caused by virus, is transmitted by mosquito?", we will analyze each option provided and determine the causative agents and modes of transmission.

### Step 1: Analyze Typhus
- **Causative Agent**: Typhus is caused by a bacterium known as *Rickettsia typhi*.
- **Mode of Transmission**: It is transmitted by the bites of arthropods (specifically fleas and lice).
- **Conclusion**: Typhus is caused by bacteria, not a virus. Thus, it cannot be the correct answer.

### Step 2: Analyze Rocky Mountain Fever
- **Causative Agent**: Rocky Mountain Fever is caused by the bacterium *Rickettsia rickettsii*.
- **Mode of Transmission**: It is transmitted by the bites of infected ticks.
- **Conclusion**: Rocky Mountain Fever is also caused by bacteria, not a virus. Therefore, it is not the correct answer.

### Step 3: Analyze Yellow Fever
- **Causative Agent**: Yellow Fever is caused by a virus that belongs to the genus *Flavivirus*.
- **Mode of Transmission**: It is transmitted through mosquito bites.
- **Conclusion**: Yellow Fever is caused by a virus and is transmitted by mosquitoes, making it a potential correct answer.

### Step 4: Analyze Filaria
- **Causative Agent**: Filaria is caused by roundworms (specifically filarial worms).
- **Mode of Transmission**: It is transmitted by the bites of black flies or mosquitoes.
- **Conclusion**: Although Filaria is transmitted by mosquitoes, it is caused by roundworms, not a virus. Therefore, it is not the correct answer.

### Final Conclusion
After analyzing all the options, the only disease that is caused by a virus and transmitted by mosquitoes is **Yellow Fever**.

### Answer:
The correct answer is **Yellow Fever**.

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