Paragonimus is a lung fluke (flatworm) that infects the lungs of humans after eating an infected raw or undercooked crab or crayfish. Less frequent, but more serious cases of paragonimiasis occur when the parasite travels to the central nervous system. Paragonimiasis affects roughly twenty-two million people worldwide, but it is particularly prevalent in East Asia due to the practice of eating undercooked or pickled crustaceans that may be carrying the metacercariae of P. westermani.
Paragonimus infections are treatable by your health care provider. Prescription medications are available. Results may remain positive for as long as 20 years after cure. Further research is being conducted to determine the drugs for the Paragonimus and how long it can affect humans.