Roundworm—Angiostongylus (also called the Rat Lungworm) causes Angiostrongyliasis which affects the abdomen but can migrate to the nervous system causing headaches, stiff neck and back, meningitis, seizure and paresthesia. They can also get into the eyes causing vision disturbances. Angiostrongylus is passed by snails, slugs, planaria, fish, land crabs and rats. Make sure you thoroughly wash greens and cook your snails before eating them.
Diagnosis is through muscle or tissue biopsy.
LifeCycle of Angiostrongylus:
Reference: https://www.dpd.cdc.gov/dpdx/HTML/Angiostrongyliasis.htm