The
bronchial or
lung fluke; a
species that causes paragonimiasis, found chiefly in Japan, Korea, Taiwan, China, the Philippines, and Thailand;
eggs are coughed up in
sputum or swallowed and passed in the faeces; miracidia
invade Melania snails, and manufacture
big numbers of stumpy-tailed cercariae that
leave the
snail and crawl
into muscles and
viscera of
crayfish or
crabs and encyst; in humans the excysted worms
invade the
wall of the
gut and
migrate through the
diaphragm into the lungs; the developing parasites
reason an intense
inflammatory reaction and eventually
induce fibrous-walled nodules that generally contain a
pair of
adult worms, along with exudate, eggs, and remains of
red blood cells; the fibroparasitic nodules may
become contiguous and
form multiloculated cystlike structures; in some instances, the flukes
involve the brain, liver, peritoneum, intestine, or skin.
Synonym: Paragonimus ringeri.