Download - TAPEWORMS: GENERAL CHARACTERS
TAPEWORMS:
GENERAL CHARACTERS
“Mkhitar Gosh” University, Armenia
Medical biology courses : Lecture N 25
Cestodes (Greek Kestos — girdle or ribbon) are
segmented tape-like worms whose sizes vary from a few
millimetres to several metres. The adult worm consists of three
parts — the head, neck and trunk. The head (scolex) carries
grooved or cup-like suckers, which are the organs of
attachment to the intestinal mucosa of the definitive host,
human or animal. The neck, immediately behind the head is
the region of growth, where the segments of the body are
being continuously generated. The trunk (called strobila) is
composed of a chain of proglottides or segments. The
proglottides near the neck are the young immature segments,
behind them are the mature segments and at the hind end are
the gravid segments
EPIDEMIOLOGY
T. solium is found everywhere in the world. However,
prevalance of T. solium are high in Mexico, Central and
South America, Africa, Asia, Spain, and Portugal. Areas of
poor sanitation, large fecal human contamination, and areas
where pigs or swines graze have high rates of T.solium
infection. Countries where people like to eat their meat
undercooked (like some parts of Europe and Asia) also have
high infection rates. Taeniasis and cysticercosis are very rare
in Muslim countries.
Cysticercosis outside the central nervous
system is treated surgically. For patients
with ocular cysticercosis, the cysts are
removed. Excisonal biopsies are
performed on subcutaneous cysticercosis.
For patients with brain cysticercosis, two
drugs praziwuantel and albendazole are
relatively successful as treatments. The
prognosis for a patient with adult
tapeworms that can be removed surgically
or medically treated is good. The
prognosis for patients with racemose form
of the parasite is bad.
Indicate the system which Cestodes have not:
A digestive system
B excretory system
C nervous system
D respiratory system
E genital system
What is the characteristic feature of gravid proglottid of
Taenia solium?
A 17 –35 uterine branches
B 7 –12 uterine branches
C bilobed ovary
D trilobed ovary
E gravid uterus is in the form of rosette