Diagnosis

Trichinella larvae travel from the small intestine through the arteries to bury themselves inside muscle tissue, so stool sample tests don't often show evidence of the parasite. Your doctor can diagnose trichinella infection by performing a physical exam and discussing your signs and symptoms such as swelling around the eyes, muscle inflammation and fever.

To confirm the diagnosis, your doctor might use these tests:

• Blood tests. Your doctor may take a blood sample and test it for signs suggesting trichinosis — an increase in the number of a certain type of white blood cell (eosinophils) or the formation of antibodies against the parasite after several weeks.
• Muscle biopsy. While a blood test typically is enough to establish a diagnosis, your doctor might also recommend a muscle biopsy. A small piece of muscle is removed and examined under a microscope to look for trichinella larvae.