A mosquito borne viral disease is

Options

A. Malaria and Chaga's disease
B. Yellow fever and Dengue
C. Filariasis and Typhus
D. Kala-azar and Diphtheria

Answer

To determine which option represents a mosquito-borne viral disease, we will analyze each option provided in the question.

### Step-by-Step Solution:

1. **Understanding Mosquito-Borne Diseases**:
- A mosquito-borne disease is one that is transmitted by mosquitoes and caused by a virus.

2. **Analyzing the First Option: Malaria**:
- Malaria is caused by a parasite known as Plasmodium, not a virus. It is transmitted by the female Anopheles mosquito.
- **Conclusion**: Malaria is not a viral disease. **(Incorrect option)**

3. **Analyzing the Second Option: Chagas Disease**:
- Chagas disease is caused by the parasite Trypanosoma cruzi and is transmitted by the triatomine bug, not a mosquito.
- **Conclusion**: Chagas disease is not a viral disease and is not transmitted by mosquitoes. **(Incorrect option)**

4. **Analyzing the Third Option: Yellow Fever**:
- Yellow fever is caused by the yellow fever virus and is transmitted by the Aedes mosquito.
- **Conclusion**: Yellow fever is indeed a mosquito-borne viral disease. **(Correct option)**

5. **Analyzing the Fourth Option: Dengue**:
- Dengue fever is caused by one of four dengue viruses (DEN1, DEN2, DEN3, DEN4) and is also transmitted by the Aedes mosquito.
- **Conclusion**: Dengue is also a mosquito-borne viral disease. **(Correct option)**

6. **Analyzing Other Options: Filarisis and Kalazar**:
- Filarisis is caused by parasitic roundworms and is not a viral disease.
- Kalazar (Leishmaniasis) is caused by the Leishmania parasite and is also not a viral disease.
- **Conclusion**: Both are incorrect options.

### Final Answer:
The correct answer is that mosquito-borne viral diseases include **Yellow Fever and Dengue**.

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