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==schistosoma is distinct from other trematoda==
*trematode中schistosomaは他のtrematodeと異なる特徴を持つ
|does not require 2nd intermediate host<br>(no metacercariae stage)||requires 2nd intermediate host
|}
==distribution==
[[File:Schistosomiasis distribution adapted from Ferarri, Lancet Neurol 2011.jpg|500px]]
==lifecycle==
{{Intermediate
|category=snails
|latin=''Oncomelania nosophora'' 宮入貝 in Japan
|inward=
<ol>
<li>eggs hatch in freshwater to '''miracidia'''
<li>miracidia invade snail tissue
</ol>
|organ=snail tissue
|reproduction=asexual
|course=
<ol>
<li>miracidia grow into '''sporocysts''' in snail tissue
<li>sporocysts release '''cercariae''' in snail tissue
|detection=
|outward=cercariae swim into freshwater in reaction to light (sunlight)
}}
{{Definitive
|category=human being
|latin=
|inward=
<ol>
<li>cercariae '''penetrate skin''' of human who put body into contaminated freshwater
<li>cercariae lose their tail during skin penetration and become '''schistosomulae'''
<li>schistosomulae enter into circulation and migrate to specific organ to grow up to adults
|organ=
<ul>
<li>venous plexus of urinary bladder in case of ''S. haematobium''
<li>portal vein through liver in case of other spp.
|reproduction=sexual (different from other trematodes)
|course=
<ol>
<li>adults differentiate to male and female
<li>both mate in portal vein and live veins of the organ for decades
<li>mated female produce egg inside veins
*'''eggs obstruct veins and induce inflammatory reaction to cause disease'''
|detection=
<ul>
<li>microscopic detection of eggs in urine (''S. haematobium'') or feces (other spp.)
*'''Kato-Katz technique''' for feces
<li>serological detection of protein of eggshell
*'''circumoval precipitin test (COPT)'''
|outward=
<ol>
<li>eggs are released into freshwater from urine or feces
<li>eggs hatch in freshwater and invade snail tissue
}}
==''Schistosoma japonicum''==
*Katsurada Fujiro found 26 May 1904 from a cat in Yamanashi（水腫腸満）
*Fujinami Kan found 30 May 1904 from a murder victim in Katayama, Hiroshima（片山病）
*found ova egg in 1904 in Saga（奇病） *[https://www.youtube.com/watch?v=3Glf6GPPZ6w YouTube: Japanese schistosomiasis]
==pathogenesis==
*ova produced adult female paired by female adult within male migrate to messenteric vein from portal vein and lay eggs into messenteric venule, which are secreted from messenteric venule to intestinal lumen*eggs also reach urinary bladder or genital tract and generate inflammation, followed by necrosis of tissue and perforation to intestine, resulted in extracorporeal distribution of ova egg via stool*eggs are also distributed in liver and cause inflammation resulting in cirrhosis*inflammation is exclusively due to ovaegg
*'''adult pairs do not cause disease per se'''
==co-infection==
*HIV
*'''Typhoid'''
**''Salmonella'' typhi has '''crossover antigenicity with ''Schistosoma''''' and makes '''immune-tolerance against ''Schistosoma'' infection'''
**Also '''''Salmonella'' hide''' between male and female schistosomes in the '''gynecophoric canal'''
*HepB/C
==treatment==
*praziquantel was discovered only in mid-1970s in Germany
*praziquantel only kills adult schistosoma
==control==
*In Japanese history before introduction of praziquantel, one of ways to control was eliminate intermediate hosts, snails - ''Oncomelania nosophora'' 宮入貝
*After introduction of praziquantel
#Malacological monitoring of snails in endemic area
#Improve water irrigation in order to avoid colonization of snails
#Effective screening of people in endemic area to detect actively infected patients
#Periodical mass drug administration to people in endemic area
*Praziquantel 30mg/kg twice for MDA
*Praziquantel 60mg/kg in two divided dose for detected patients
