schistosoma japanicum

1. schistosoma
japonicum
Ghufran Ahmed

2. schistosoma japonicum :
A species of trematode worm that parasitizes humans and
that causes liver and gastrointestinal tract disease.
• is the most pathogenic of all the human schistosome species.
It occurs in parts of China, Japan, the philippines, and
Indonesia

3. Habitat
Definitive Host :
-Humans
Intermediate Host :
-Freshwater snails
Epidemiology
• prevalent in tropical and subtropical areas “especially in
poor communities without access to safe drinking water
and adequate sanitation”
H
Hi

4. Life Cycle Of Schistosoma Japonicum

5. Morphojogy :
• Egg:
• Shape: round or oval
• Size:80 by 60 mm
• Small spur on one end
• Larva - Miracidium :
• Hatches from egg
• Free swimming
• Ovoid
• Covered with cilia
• Complex of glands at the front end

6. • Sporocyst:
• Metamorphoses
• No mouth or gut
• Reproduces asexually (twice)
• Creating daughter sporocysts
• Cercaria (offspring)
• Larva - Cercaria:
• Size: 200 by 70 mm
• It has two “FLUKES”
• Adult Flukes:
• Size: 15 mm in length
• Males are shorter & stouter than females
• Males have a long groove on their underside
• Female resides in that groove
• Both have a sucker aroud the mouth called an acetabulum

9. Transmission:
: Penetration in to the skin
• Via fecal –dermal route , or urinal – dermal rout

10. Pathogenesis:
• he schistosoma japonicum’s life cycle starts when the eggs are
eliminated with feces, hatch in the water and release the larvae
(miracidia) that are viable for up to seven days until they penetrate
the snail oncomelania14. In the snail there will be two generations of
sporocysts and cercariae.
• Once released from the snail, the cercariae will swim and penetrate
through the skin, shed the tail and become a schistosomulae; they
become adult worms and migrate to the mesenteric venules of the
small and large intestine14. Finally, the circle starts again when the
eggs move toward the lumen of the intestine and pass with the
feces. This life cycle includes snails, domestic and wild animals
which makes its control and prevention more complicated; therefore,
treating the infection and reducing the oncomelania snail burden is
not enough

11. The physiopathology of chronic schistosomiasis results
from the eggs lodging, inducing immune response,
granuloma formation, fibrotic changes, damaging the
organs and tissues of the human host16. Adult worms
absorb host proteins so if not attacked by the immune
system, they can live coated with host antigens for
years17. The shed eggs penetrate the bowel adjacent to
mesenteric vessels, whereas unshed eggs go back to
portal circulation, lodge and induce granulomatous
reaction16. In the liver the chronic progression causes
periportal fibrosis, called Symmers piperstem fibrosis, if left
untreated it will lead to portal hypertension with all the
cirrhosis complications

12. • Clinical Findings
Acute Stage:
 Mostly asympotomic
 Itching
 Dermatitis
 Followed 2- 3 weeks by :
• fever
• Chills
• Diarrhea
• Lymphadenopathy
• Hepatosplenomegaly
 Esinophilia
Chronic Stage:
 Gastrointestinal hemorrhage
 Hepatomegaly
 Massive splenomegaly
 Death

14. Dignosis
• SAMPLE:
 Sputum, Urin( concentration techniques ) ,Feces( fecal smear)
• MICROSCOPY:
 Charactreristic ova
 Spines: Rudimentary spines
• LFTs
• SEROLOGICAL TEST
• BLOOD TEST
 Moderate eosinophilia

15. Treatment
• Acute stage usually resolves spontaneously
• Praziquantel
Prevention
• Proper disposal of human wastes
• Eradication of snail hosts
• Avoid swimming in areas of endemic infection

16. Thank you for listening
If you have any information or question
do not hesitate to ask