Trichuriasis
If infection is only with a
few worms, there are often
no symptoms.
In those who are infected
with many worms, there
may be abdominal pain,
tiredness and diarrhea. The
diarrhea sometimes
contains blood
Giant
roundworm
Ascaris
lumbricoides
(ova)
Ascariasis
Symptoms of abdominal
swelling, abdominal pain
and diarrhea.
PARTS OF
THE BODY
INFECTED
Human large
intestine
Wall of
the duodenu
m and enters
the blood
stream
liver
heart
respiratory
system
small
intestine
STAGES OF THE LIFE
CYCLE OBSERVED
Estimates of egg production
range from 1,000 to 7,000 per
day. Embryonation is
completed in about 21 days in
soil, which must be moist and
shady. When swallowed, the
infective juvenile hatches in the
small intestine and enters the
crypts of Lieberkuhn. After a
short period of development, it
reenters the intestinal lumen and
migrates to the ileocecal area
where it matures in about 3
months. Adults live for several
years, so large numbers may
accumulate in a person.
A. lumbricoides, a roundworm,
infects humans when an
ingested fertilised egg becomes
a larval
worm (called rhabditiform
larva) that penetrates the wall of
the duodenum and enters
the blood stream. From there, it
is carried to the liver and heart,
and enters pulmonary
circulation to break free in
the alveoli, where it grows
and molts. In three weeks,
the larva passes from
the respiratory system to be
coughed up, swallowed, and
thus returned to the small
intestine, where it matures to an
adult male or female
worm.Fertilization can now
occur and the female produces
as many as 200,000 eggs per
day for a year. These fertilized
eggs become infectious after
two weeks in soil; they can
persist in soil for 10 years or
more.
The eggs have a lipid layer
which makes them resistant to
the effects of acids and alkalis,
as well as other chemicals. This
resilience helps to explain why
this nematode is such a
ubiquitous parasite.
Beef
Tapeworm
Taenia
saginata
Taeniasis
generally asymptomatic,
but severe infection
causes weight
loss, dizziness,abdominal
pain, diarrhea, headaches,
nausea, constipation, chron
ic indigestion, and loss
of appetite.
muscle, liver
, and lungs of
cattle into
infective
cysticerci.
The life cycle of T. saginata is
indirect and digenetic, involving
cattle and humans, with an
interim of living in the
environment. Humans as
the definitive host harbour adult
worms which release infective
eggs into the environment
through defecation. Cattle as
the intermediate host pick up
the viable eggs from
contaminated vegetation.
Pork Tape Taenia
solium
worm
Taeniasis
generally asymptomatic,
but severe infection
causes weight
loss, dizziness,abdominal
pain, diarrhea, headaches,
nausea, constipation, chron
ic indigestion, and loss
of appetite.
muscle, liver
, and lungs of
cattle into
infective
cysticerci.
The life cycle of T. solium is
indirect. It passes through pigs,
as intermediate hosts, into
humans, as definitive hosts.
From humans, the eggs are
released in the environment
where they await ingestion by
another host. Humans as the
definitive hosts are directly
infected from contaminated
meat.
Pinworm
Enterobiu
s
vermicular
is
pinworm
infection or enterobi
asis
The chief symptom is
itching in the anal area