Download 毛首鞭形线虫

毛首线虫
Trichuris sp.
主讲: 刘园
组员：刘园 胡伟高 江保祯 皮瀛江
毛首线虫
Trichuris sp.
Whipworm(鞭虫），a kind of common
nematodes(线虫） in pig and human，the
adults of whipworm live in colon of pig，
cause trichuriasis(鞭虫病）。
一、形 态（Morphology）
1.成虫（adult）
Like whip, the front 3/5 is slender，the end
2/5 is bulky.
The females are big，the end of male is
round and straight.
The males
are small，♀
the end of ♂
male bends
♀
to venter.
♀long，about 45cm
♂
♂
♂short，about
3-4cm
♀
♂
♀
♀
The end of the male
has a spicule(交合刺)
2. 虫卵（ Egg）:
 spindle(纺锤形)
 tan
(黄褐色)
 50-54×22-23µm
Egg shell is thick，and
has plug(栓塞) at each end.
The egg in Electronic microscope
Spindle shaped with two plug-like prominence at two poles
二、生活史（life cycle）
Three weeks
egg
（warm, wet）
（develop in soil for 3 week）
（develop in human body
for 60 days）
adult
（colon）
To colon
（about 10 days）
From mouth--- small
intestine
（feces）
egg in
infectious
period
juvenile
worm
Trichuris suis life cycle
（猪毛首线虫生活史）
Direct life cycle
Infective stage:
infective egg
By ingestion
三、 致 病（Pathogenesis）
The head of adults bore into intestinal mucosa，
and feed on tissue fluid and blood of the host。
Mechanical damage
The stimulation of
secretion
intestinal mucosa congestion (充血）
hemorrhage（出血） engorgement（肿
胀）
Note:If infection is not serious, the symptoms above
don’t exist.
Parasitism in the colon
四、诊断（Diagnosis ）
Etiologic diagnosis：
Direct Smear
Fecal Flotation
五、流行（ Epidemiology）
Worldwide, with infections more frequent
in areas with tropical weather and poor sanitation
practices, especially among piglets and children.
Infected pigs and persons are the important
source of infection.
六、防治（Treatment and control）
1.
2.
3.
4.
Periodic deworming
Improve sanitation
Healthy education (human)
Harmless disposal of feces
summary
• The nematode Trichuris sp., also called the whipworm.
•
Geographic Distribution: Worldwide, with infections more frequent
in areas with tropical weather and poor sanitation practices, and
among children.
• Infection occurs through accidental ingestion of eggs (which are
usually found in food and water.)
• Final diagnosis: Trichuriasis can be diagnosed when the eggs are
detected in stool examination.
• Treatment and control: Metronidazole is 90% effective in the first
dose, and albendazole may also be offered as an anti-parasitic agent.