The disease may include 1/ Nausea, dysentery, colic due to invasion by adult worms, 2/ Migrating juveniles cause pain as they invade muscle tissue; there may also be edema (swelling), delirium, cardiac and pulmonary difficulties, pneumonia, nervous disorders, deafness and delayed or lost reflexes, and 3/ Many cases are never diagnosed because of the vagueness of the symptoms. Muscle biopsy can be conducted and sometimes involves pressing muscle between glass plates to look for cysts. Xenodiagnosis involves feeding suspected muscle to laboratory rats.