Mary Mallon was a cook by profession and also a carrier of a particular disease. Which test is commonly used for diagnosis of this disease?

Options

A. Monteaux test
B. Widal test
C. Western blot
D. ELISA

Answer

To solve the question regarding the diagnosis of the disease associated with Mary Mallon, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Disease**: The question mentions Mary Mallon, who is famously known as "Typhoid Mary." This indicates that the disease in question is typhoid fever.

2. **Understand the Nature of the Disease**: Typhoid fever is caused by the bacterium *Salmonella typhi*. It is important to know that this is a bacterial infection.

3. **Review Diagnostic Tests**: The question provides four options for diagnostic tests:
- Monty ox test
- Vidal test
- Western blot
- Elisa test

4. **Evaluate Each Option**:
- **Monty ox test**: This is not a recognized test for typhoid fever.
- **Vidal test**: This is a serological test specifically used to diagnose typhoid fever by detecting the presence of antibodies against *Salmonella typhi*.
- **Western blot**: This is primarily used for detecting specific proteins and is not typically used for diagnosing typhoid.
- **Elisa test**: While this test can be used for various infections, it is not the primary test for typhoid fever.

5. **Select the Correct Answer**: Based on the evaluation, the most appropriate test for diagnosing typhoid fever is the Vidal test.

### Final Answer:
The commonly used test for the diagnosis of typhoid fever, which Mary Mallon was a carrier of, is the **Vidal test**.

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