Which one of the following disease is not transmited by mosquito?

Options

A. Brain fever
B. Malaria
C. Typhoid
D. Dengue

Explanation

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks which disease is not transmitted by mosquitoes among the options provided: brain fever, malaria, typhoid, and dengue.

2. **Analyzing Each Option**:
- **Brain Fever**: This disease includes conditions like Japanese encephalitis, which is transmitted by mosquitoes. Therefore, it is transmitted by mosquitoes.
- **Malaria**: This disease is caused by the Plasmodium protozoan, which is transmitted through the bite of infected female Anopheles mosquitoes. Hence, malaria is also transmitted by mosquitoes.
- **Typhoid**: This disease is caused by the bacterium Salmonella typhi and is transmitted through the consumption of contaminated food and water. It does not require a mosquito vector for its transmission.
- **Dengue**: This disease is caused by the dengue virus, which is transmitted by the bite of infected Aedes mosquitoes. Thus, dengue is transmitted by mosquitoes.

3. **Identifying the Correct Answer**: Among the four options, typhoid is the only disease that is not transmitted by mosquitoes. The other three diseases (brain fever, malaria, and dengue) are all transmitted by mosquito bites.

4. **Final Answer**: Therefore, the correct answer is **typhoid**.

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