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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''==
*inflammation is exclusively due to egg
*'''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==
*only way In Japanese history before introduction of praziquantel, one of ways to control is 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
