What is eosinophilia? How does it occur?

Explanation

### Step-by-Step Solution:

1. **Definition of Eosinophilia**: Eosinophilia is a medical condition characterized by an increased number of eosinophils in the bloodstream. Eosinophils are a type of white blood cell that play a crucial role in the immune system.

2. **Role of Eosinophils**: Eosinophils are involved in the body's immune response, particularly in fighting infections and responding to allergens. They help combat parasitic infections and are also involved in allergic reactions.

3. **Mechanism of Eosinophilia**: Eosinophilia occurs when there is an increase in the production of eosinophils. This increase can happen due to various stimuli, such as infections, allergies, or other medical conditions.

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