1. FASCIOLOPSIS BUSKI

2. Introduction largest intestinal fluke in humans.Infection occurs
Fasciolopsis buski is known scientifically as the
largest intestinal fluke in humans.Infection occurs
primarily in Asia and the Indian subcontinent,
especially in area where humans raise pigs and
consume freshwater plants, so this helminth is also
named as “giant Asian intestinal fluke”.This giant
parasite has even been described as “meat worm”
or “reddish worm” in traditional Chinese medical book.

3. I. Morphology (1) Adult Long elliptic, flesh-colored, looks like
a slice of raw meat
The size: 20-75×8-20×0.5-3mm
The ventral sucker (filler-like
/ infundibular ) is larger and near by the
much smaller oral sucker
Two coral-liked(珊瑚) testes are located
in the posterior half of the body
No seminal receptacle

4. uterus ventral sucker is 3-4 times larger than oral sucker oral sucker
cecum
ovary
vitellaria
testes

5. (2) Egg The thinner shell with an operculum (not so obvious)
encloses an ovum
and yolk cells
Slightly yellow in color
×80-85µm (the largest helminth egg)
Oval / long elliptic in shape

7. The first intermediate host：
Segmentina

8. The second intermediate host： Aquatic plant vector
water caltrop水红菱
茭白cane shoot
Water chestnut荸荠
The second intermediate host：
Aquatic plant vector

9. II. Life cycle Site of inhabitation: small intestine,
2. Infective stage: metacercaria,
3. Infective route and mode: eating raw water
plants with metacercariae,
4. Intermediate hosts: Planorbis snail,
5. Reservoir hosts: pig,
6. Life span: 1-4 years,
7. Egg output: 15,000/worm/day.

10. man eats metacercariae in feces ────────────────────────────
Adolescent Adult Eggs
Duodenum In Human Body
3 months are discharged
man eats metacercariae in feces
on raw water plants
────────────────────────────
Metacercaria Eggs get into water
encystations on the In Water ℃
surface of water plants months weeks
Miracidia hatch out
invades
Many cercaria asexual reproduction Planorbis snail
Many daughter rediae Many mother rediae Sporocysts

11. III. Pathology and Symptomatology
The enteritis due to worms’ adhesion manifests abdominal discomfort and
diarrhea.
2. Malnutrition results from the worms
sharing food with the host and diarrhea.

12. IV. Diagnosis 1. Direct fecal smear, 2. Water sedimentation method
Stool examination:
1. Direct fecal smear,
2. Water sedimentation method

13. V. Treatment and Prevention
1. The treatment of the patients, carriers and pigs
Drug of choice is praziquantel. Other effective
drugs include hexachloroparaxylene, bithionol (bitin).
The drug for pig is dipterex (敌百虫).
2. Prevention
(1) Health education
(2) Deal with night soil.
(3) Avoid feeding pigs on raw water plants

14. VI. Epidemiology This disease is prevalent in Southeast
Asia,China, Japan, Korea, Thailand, Burma, Kampuchea, Vietnam, Bangladesh, Philippines,Indonesia, Malaya and India
. In China it is found in 18 provinces, city and
autonomic region except north and west regions.
The prevalence of fasciolopiasis is relative to growing water plants and feeding pigs
on water plants.

15. Thank you !