學名細粒棘球絳蟲(Echinococcusgranulosus)

成蟲寄生在狗、狼等食肉類動物體內(nèi)

幼蟲稱棘球蚴，寄生在食草類有蹄動物體內(nèi)

幼蟲可寄生在人，引起棘球蚴病(echinococcosis,hydatiddisease)

E.granulosus,thespeciesresponsibleformostcasesofinfectionEchinococcosis,theinfectioniscausesalsoisknownascystichydatiddisease.Adultwormingastrointestinaltractofcarnivores,larvalstageinherbivorousanimalsandhumanbeing.Echinococcusgranulosus

Morphology

(1)成蟲：絳蟲中最細小的一種，2～7mm長。

(2)蟲卵：與帶絳蟲卵相似

(3)棘球蚴(hydatidcyst)adult:small,consistsofscolex,neckandthreeproglottides,oneateachdevelopmentalstage:immature,matureandgravid.scolexcontainfoursuckers,hooks

egg:similarwithotherTaenia

smalltapeworm–2～7or3～7mmlong,consistsofscolex,neck,immatureproglottid,matureproglottid,andgravidproglottid

1.囊壁：(1)外層－角皮層：乳白色，無細胞結(jié)構(gòu)，具保護囊內(nèi)容物和滲透、吸收營養(yǎng)作用。(2)內(nèi)層(germinallayer)：胚層，具生發(fā)作用，單細胞層，向外分泌角皮層，向內(nèi)生成育囊(broodcapsule)、原頭節(jié)(protoscolex)(3)囊內(nèi)容物育囊：無角皮層子囊棘球砂游離于囊內(nèi)物質(zhì)，包括原頭節(jié)、子囊、育囊，稱棘球砂，一個原頭節(jié)可以再形成棘球蚴，或入終宿主發(fā)育為成蟲假囊壁：是炎癥反應(yīng)的宿主組織Hydatidcyst:Wheneggisingestedbyintermediatehost,includingperson,theliberatedembryopenetratestheintestinalwall,passesintothelymphaticsormesentericvenules,andiscarriedbythebloodstreamtovariouspartsofthebody.

Itgrowsslowly&requiresseveralyearsfordevelopment.afluid-filledbladder

containeddaughtercysts,broodcapsules

surroundedbyaprotectivecystwall,

laminatedmembranegerminallayer

ahydatidsandmayevolveinthefluidofoldercyst,broodcapsules,daughtercyst,protoscolex

laminatedmembranelaminatedmembranegerminallayergerminallayerbroodcapsuledaughtercysthydatidsandbroodcapsuleprotoscolex棘球蚴假囊壁棘球蚴角皮層胚層育囊子囊原頭節(jié)adultsliveincaninesmallintestine 100s-1000sofwormsinupperhalfofsmallintestine release100sofinfectiveeggsinfeceslarvalstageinfection(sheep,cattle,pigs,horses&humans)

acquiredbyingestingembryonatedeggs

oncospherehatchesinsmallintestine

bloodstreamliverviaportalcirculation

otherorganscanbeinvaded(lung,brain&kidney)larvasurroundedbyhyalinemembrane

outernon-cellularstructure&innergerminallayer germinallayergivesriseto:

protoscolices(infectiousstagefordefinitivehost) moreoutermembranematerialcystdevelops,matures&fillswithfluid(monthstoyears)LifecycleLifecycleAdultwormofE.granulosusliveinthesmallintestineofadefinitivehostHumanaretheintermediatehost,carryingthehydatidcyst

SheeparethemostcommonintermediatehostforE.granulosus

Humaninfectionbeginsfollowingcontactwithcontaminateddogfeces

oncosphereshexacanthembryohydatidcysttissueofhumanAdultwormeggorgravidingestedhexacanthpenetrateintestinehydatidembryoenterveinsystemcystingestedbycarvivores

成蟲

孕節(jié)

六鉤蚴

棘球蚴污染牧草侵入血管人吞入六鉤蚴棘球蚴牛羊吞入狼犬吞入人感染蟲卵往往是下列情況：誤食蟲卵與狗接觸而感染剪羊毛、接生羊羔、擠奶時受污染而感染Pathogenicity壓迫和刺激

過敏和中毒破裂和細菌感染肝包蟲病、肺包蟲病、腦包蟲病、骨包蟲病并發(fā)癥：囊腫破裂(膽囊、腹腔、胸腔）－－－繼發(fā)性棘球蚴病、感染Hydatidcystcauseechinococcosis,orhydatidosisThedevelopmentofclinical&symptomsdependsonthesizeofthecystandtheorgansinvolved

symptomsarefromlarge,space-occupyinglesionoverallfatality~2%~50%ofhydatidcystsasymptomaticcystrupture(minorblunttrauma)leadstoanallergicreaction maybemild&limitedtourticaria maybeanaphylacticshockliveresenlarged uninvolvedpartofliverremainsnormal ruptureoflivercystsintobiliarytreelung bloodysputumcontainsprotoscolicesorhooklets ruptureintobronchialtreePathogenicityAhepaticlesionmaybeasymptomaticforaslongas75years(66%)

Hydatidcystsgrowfasterinlung(22%)&brain(2%)secondaryinfection

rupture(secondarycyst,allergicreaction)UnilocularhydatidcystinthelungNotepressureeffectsexertedbycystthatcrowdsanddestroyslungtissue

6inchunilocularhydatidcystthatkilleda7year-old-girlinColorado，USADiagnosis

1.詢問病史2.免疫學3.Ｘ線、CＴMRI4.基因診斷

ahistoryofresidenceinanendemicarea,closecontactwithdog

X-ray,CT,MRISerologicaltest(skintest,IHA,ELISA)PCRismorespecificfordistinguishingdifferent

Echinococcusspecies

KeypointsPresumptivediagnosismaybebasedonhistory,radiographicstudies,orscansAdditionalsupportivedatamaybeacquiredfromimmunologictestsMicroscopicexaminationofhydatidcystfluidmayrevealthehydatidsandor,undercertaincircumstances,justthehookletsLight,fluorescence,andepi-fluorescencemicroscopycanbeusedtovisualizethehooklets;someapproacheswillrequirestaining,somewillnotEpidemiology

造成流行的原因：１.病犬、狼排泄物污染牧草，羊、牛吞入感染，人也可誤食入。２.病牛、羊的內(nèi)臟或病羊被狗或狼吞噬而感染。

３.蟲卵抵抗力強。

foundinsheep-raisingarea

carnivoresaredefinitivehostsherbivoresareintermediatehosts

humaninfectionsresultingfromingestionofeggs

manisa‘deadendhost’fortheparasiteHumanscontracttheinfectionbyingestingeggsoftheparasiteinthefecesofthedefinitivehostContaminatedfoodorwateristhecommonrouteoftransmission,butdirectcontactwiththedefinitivehost,alsoisanimportantwaytoacquireinfection

Eggswithhighresistant

Prevention&control注意個人衛(wèi)生，防止蟲卵入預(yù)防犬感染治療病人albendazole或手術(shù)

PAIR（PercutaneousAspiration,Injection,Re-aspiration)Surgicalremovalofthecystisindicatedinallcasesshowingsymptomsofthedisease

Themedicationmebendazole&albendazolehaveparticularlybeenusefulinsituationswherethehydatidcystwasinoperable

TheeducationprogramforinhabitantsinareasatriskfortransmissionoftheparasiteVaccineshaveeavailableforimmunizationoftheintermediatehost多房棘球絳蟲(E.multilocularis)

幼蟲期為多房棘球蚴，人因誤食蟲卵而感染，在人體引起嚴重的泡球蚴病，主要在肝臟，呈彌漫性生長、外生型，形成腔化囊泡。１－２年可使寄生器官被大小囊泡占據(jù)，猶如惡性腫瘤，需與惡性腫瘤鑒別。EndhostLifeCycleofEchinococcusmultilocularis

Alveolarhydatidcystinamouse-cystmetastasizesfromthelivertofillthebodycavity

Alveolarhydatidcystintheliver.Notethelaminatedlayer,germinallayer,protoscolices.Comparisonofunilocularandalveolarhydatidcysts

曼氏迭宮絳蟲(Spirometramansoni)

成蟲寄生在貓狗小腸，偶爾寄生人體致曼氏迭宮絳蟲病。幼蟲則為裂頭蚴(sparganum)，可寄生在蛇、蛙體，也可寄生人體致病－裂頭蚴病(sparganosis)。Morethan300humancaseshavebeenreportedintheworldliteratureMajorendemicareasareChina,Japan,Korea,Vietnam,ThailandandotherSoutheastAsiancountries.OnHainanIsland,itisstillcommonpracticetoapplyrawfrogfleshasapoulticetotheeyeofpatientswithhighfever.一、形態(tài)成蟲60-100cm，成節(jié)、孕節(jié)結(jié)構(gòu)相似。裂頭蚴長帶形，白色，約300×0.7mm

蟲卵紡錘形，兩端稍尖，有卵蓋，卵殼內(nèi)含卵黃細胞和一個卵細胞。二、生活史需三個宿主終宿主：貓,狗第一中間宿主：劍水蚤第二中間宿主：蛙、蛇、鳥、豬為轉(zhuǎn)續(xù)宿主人可作轉(zhuǎn)續(xù)宿主、中間宿主、終宿主

成蟲卵鉤球蚴原尾蚴裂頭蚴

人既可被裂頭蚴寄生，也可被成蟲寄生。

入水2-5W劍水蚤吞入穿入血腔貓犬吞入劍水蚤三、致病裂頭蚴病人感染的方式：

1.飲用生水或游泳時誤飲湖水。

2.局部敷貼生蛙肉。

3.吞食生或半熟蛙、蛇肉。

常寄生于眼(30-45%)、皮下肌肉(31-37%)、

腦（2.3-3.1%)引起嗜酸性肉芽腫－局部腫

脹、疼痛，游走性腫塊。四、診斷

1.詢問病史

2.活檢

3.免疫學診斷，ELISA五、流行和防治分布廣，主要流行區(qū)為中國、日本、越南、泰國、東南亞國家。防治：１.衛(wèi)生宣教２.裂頭蚴－手術(shù)３.成蟲－吡喹酮TaeniasoliumandTaeniasaginataproglottidscanbedifferentiatedby孕節(jié)的子宮分支B.子宮孔的位置C.孕節(jié)的形態(tài)D.孕節(jié)的顏色E.孕節(jié)的長度Whichisnotadiseaseoftapeworms?A.中樞囊尾蚴病

B.貧血C.膽道梗阻

D.體重減輕E.腹痛Whichtapewormegginhumanstoolmightbeseenbymicroscopy?A.ClonorchissinensisB.TaeniasoliumC.EchinococcusgranulosusD.SchistosomahaematobiumE.FasiolopsisbuskiQuiz:Concerninghookworminfection,somethingincorrectdescriptionasfollow:A.HookworminfectioncancauseanemiaB.HookworminfectionisacquiredbyhumanwhenfilariformlarvaepenetrateC.HookworminfectioncanbecausedbytwokindofhookwormD.HookworminfectioncanbediagnosisbyfindingthetrophozoiteinthestoolE.HookworminfectioncanbecontrolbyavoidingcontactwithinfectivesoilWhichoffollowingparasitecouldbecausedbyselfinfection：

A．TaeniasoliumB．AscarislumbricoidesC．EnterobiusvermicularisD．LeishmaniadonovaniE．Paragonimuswesternamni1.WhichnematodedoesnotleavetheGItrackduringinfection?AscarislumbricoidesTrichinellaspiralisNecatoramericanusWuchereria