When man or other definitive host eats infected crabmeat, fish, or
vegetation, the metacercariae are ingested and hatch in the intestine.
The young worms then migrate to various organs of the host's body,
where they mature and produce eggs, which are passed with the host's feces to start
the cycle again.
c. Signs/Symptoms. Symptoms of fluke infestations vary according to the
organ affected and the severity of the infestation.
Intestinal infestations are often asymptomatic, or they may cause
abdominal pain and diarrhea.
Lung fluke infestations may cause coughing, blood in sputum, pain in the
chest, and muscular weakness.
Liver flukes may cause pain in the liver area, abdominal pain, diarrhea,
fever, anemia, and wasting of the body.
d. Treatment. Continued untreated infestation may lead to cirrhosis, jaundice,
and liver failure. The lungs, brain, or other tissue may be affected.
e. Prevention. Prevention consists in thoroughly cooking all fish, crabs, and
aquatic plants before eating them.
f. Location. The flukes are common throughout the Orient, Asia, India, parts of
South America, and many Pacific islands. Table 2-1 lists the common food-borne flukes
affecting man, according to the causative organism, the organ affected, the intermediate
hosts, and the area of prevalence.