Here's why:

* Eosinophils are a type of white blood cell that plays a crucial role in fighting parasites. They release chemicals that kill parasites and help control inflammation.

* When the body is infected with parasites, the immune system produces more eosinophils to fight the infection.

* Therefore, an elevated eosinophil count (eosinophilia) is a common sign of a parasitic infection.

However, it's important to note:

* Eosinophilia can also be caused by other factors, such as allergies, asthma, and some types of cancer.

* A doctor will need to consider the complete medical history and perform additional tests to determine the underlying cause of eosinophilia.