Widal test is used for the diagnosis of

Options

A. Malaria
B. Pneumonia
C. Tuberculosis
D. Typhoid

Explanation

**Step-by-Step Text Solution:**

1. **Understanding the Widal Test**: The Widal test is a serological test used to diagnose typhoid fever. It detects the presence of specific antibodies (agglutinins) in the blood against the bacteria Salmonella typhi.

2. **Identifying the Disease**: Typhoid fever is caused by the bacterium Salmonella typhi. It is important to recognize that this is the primary disease associated with the Widal test.

3. **Transmission of Typhoid**: Typhoid fever is typically transmitted through contaminated food and water. Understanding the mode of transmission helps in recognizing the risk factors associated with the disease.

4. **Symptoms of Typhoid**: Common symptoms of typhoid include:
- High fever (approximately 39°C to 40°C)
- Headache
- Loss of appetite
- In severe cases, it can lead to intestinal perforation and potentially death.

5. **Differentiating from Other Diseases**: Other diseases mentioned (like malaria, pneumonia, and tuberculosis) have different diagnostic methods:
- Malaria is diagnosed based on symptoms and blood tests for the parasite.
- Pneumonia is also diagnosed through clinical symptoms and imaging.
- Tuberculosis is diagnosed using the Mantoux test.

6. **Conclusion**: Therefore, the Widal test is specifically used for the diagnosis of typhoid fever.

**Final Answer**: The Widal test is used for the diagnosis of typhoid fever.

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