IntroductiontotheHelminths蠕蟲Helminthsmeansworms,multicellularorganisms.

PhylumClassNemathelminthes

Nematoda(roundworm)線蟲綱線形動(dòng)物門Platyhelminthes

Tremetoda(flatworms)吸蟲綱扁形動(dòng)物門Cestoda

絳蟲綱TheNematodes線蟲

Therearemany,manynematodes2006諾貝爾獎(jiǎng):ＲＮＡ干擾機(jī)制2002年諾貝爾獎(jiǎng)：程序性細(xì)胞死亡C.ElegansMorphologyCylindrical,non-segmented,bilaterallysymmetricalandsexesseparatePseudocele原體腔(pseudocoelom)

Thebodywall:

cuticle角皮層

hypodermis皮下層longitudinalmuscle肌層DigestivesystemMouthpharynxesophagusintestineanus咽管食管腸管肛門Reproductivesystem

malereproductivesystemTestisseminalvesicle

睪丸儲(chǔ)精囊

vasdeferens

輸精管

ejaculatoryduct

射精管

Mostfemalesusuallyhavetwoovaries，oviducts

anduterus..ovary—oviduct—uterus.ovary—oviduct—uterus..

卵巢輸卵管子宮

vulva-vagina

陰門陰道Excretorysystem

Excretoryporeisanterior.

排泄孔Noflamecellsarepresent.lifecycle

M1M2M3M4

EggL1L2L3L4Adultlarva(male&female)

KindsoflifecycleinnematodesAscarislumbricoides

Trichuristrichiura

EnterobiusvermicularisHookwormsIndirectlifecycle:intermediatehostisnecessary

TrichinellaspiralisFilariaDirectlifecycle:Intermediatehostisnotnecessary土源性線蟲（腸道線蟲）生物源性線蟲INTESTINALHELMINTHS

Ascarislumbricoides(roundworm)似蚓蛔線蟲Trichuristrichiura(whipworm)毛首鞭形線蟲Enterobiusvermicularis(pinworm)蠕形住腸線蟲AncylostomaduodenaleandNecatoramericanus(hookworms)鉤蟲

2004年第二次寄調(diào)Hookworms

Fivespeciesofhookworms:

Ancylostmaduodenale十二指腸鉤口線蟲

Necatoramericanus美洲板口線蟲Ancylostmaceylanicum錫蘭鉤口線蟲Ancylostmacaninum犬鉤口線蟲Ancylostmabrazilience巴西鉤口線蟲Adultliveintheintestineandtakebloodfromthehost,causehookwormdisease.Numberofhumansinfectedisestimatedat1.2billionwith50,000to60,000deathseachyear.國內(nèi)：

6.12%Enterobiusvermicularis(Pinworm)Almostanybodycanbecomeinfectedwiththisparasite，especiallychildren.Theworldwideinfectionisabout210million國內(nèi)：10.28%Morphology－AdultofAscarislumbricoides

thelargestnematodeparasitesofhumansCreamywhiteorpinkishincolorelongateandcylindricalFemale:measuring35cmlong,posteriorendisstraightMale:measuring25cmlong，posteriorendiscurved.Morphology－AdultsofAscarislumbricoides

Threelipsaroundthemouthin“品”typeandpossesssmallteethMorphology－AdultsofAscarislumbricoides

Morphology－AdultsofEnterobiusvermicularis

Adults:pin-like,white,smallwormFemaleshowingesophagealbulb&cephalicalae

Malewithcurvedposteriorend,Femalehasalongpointedend.咽管球頭翼Morphology－AdultsofhookwormsAdult:Slender,pinkishorcreamy-grayincolor,about10mminlength.MorphologyofNecatoramericanusBuccalcapsulecontainsapairofventralanddorsalcuttingplates.Copulatorybursacontainsspiculesthatarefuseddistally.shape“c”,1cm±“s”,1cm±buccalcapsuleflatandoval-shapeoval-shapetwopairsonepaircuttingplatesCopulatorybursaroundoblatespiculetwo,separatedtwo,fusedattheirends

A.duodenale

N.americanusDifferencebetweenA.duodenaleandN.americanusMorphology－larvaofhookworms

rhabditiformLarva桿狀蚴

filariformlarva:infectivestageEggsareunembryonatedwhenpassedinthefeces.Embryonationoccursinthesoil.UnembryonatedegginfecesbroadlyovalyellowishtobrownincolorThickshellovumproteincoatfertilizedMorphology－EggsofAscarislumbricoides

unfertilizedandfertilized

egg

Decorticatedegg(lostouteralbuminouscoating)EmbryonatedegginsoilMorphology－EggsofAscarislumbricoides

Morphology－EggsofTrichuristrichiura

size:50-54μmby22-23μm,smallerthanAscarids’Shape：atypicalbarrelColor：yellow-brownunstainedtwopolarplugsShell：

quitethick

Contains：

unembryonatedeggMorphology－EggsofEnterobiusvermicularissize:smallerthanAscarids’Shape：oval,flattenedononesideColor：colorlessShell：

quitethick

Contains：anundevelopedlarvainsideShape:oval-roundShell:thinwithsmoothandcolorless(transparent)eggshellSize:57-76μmby35-47μmContains:clearspacebetweentheegg-shellandtheovum.Usually2to16cellsinfecesMorphology－EggsofhookwormsMorphology－EggsofhookwormsLifecycle

LifecycleofAscarislumbricoides

Adultegginfectiveegglarva

IngestedbymanmigrationLifecycleMigrationoflarvainthehost:Vesselsofintestineliverheartlungs

trachea

pharynxintestine(swallowed)LifecycleofhookwormLifeCycle

Adulteggrhabditiformfilariformlarvalarva

Swallowedpharynxtrachealungcirculation

Penetrateskin

LifecycleofEnterobiusvermicularis

Lifecycle

ingestedAdultegginfectiveegg(inlumenofcecum)PathogenesisPathogenesisofAscarislumbricoides

larvae:AscarisPneumonitisAsthmaLarvainsectionoflungPathogenesis2)Adults：

(1)Malnutrition(2)Disorderofdigestivesystem:maincomplaint---abdominalpain(3)Allergicresponses

anorexia(食欲不振)nausea(惡心)vomiting(嘔吐)diarrhea(腹瀉)Complication并發(fā)癥

penetratetobileductspenetratetothepancreaticandtheappendix膽道蛔蟲癥胰腺闌尾intestinalobstruction腸梗阻

Ectopicparasitism異位寄生1.causeirritation(pruritus搔癢)oftheanalregionSecondarybacterialinfectioninareasscratchedrawmayoccur.vaginitisandrarelysalpingitisinyounggirls.

陰道炎輸卵管炎3.causementalanguishPathogenesisofEnterobiusvermicularis

Pathogenesisofhookworm1.Localdermatitis(grounditch)鉤蚴性皮炎

2.Pulmonary(pneumonia-like)symptoms(symptomsarenotassevereasAscarismigration)3.Anemia

a.Thewormsucksbloodandthewoundoozesblood

A.duodenaletakes0.26ml/day;N.americanus0.03ml/dayb.Thewormusuallychangesitssuckingsitec.Disfunctionofintestinetoabsorbirongraduallyproduceaniron-deficiencyanemiagastroentericsymptoms胃腸道癥狀

Slight,intermittentabdominalpainAberrationofappetite(geophagy異嗜癥).lossofnormalappetiteanddesiretoeatsoilorun-normalmaterials6.Hookwormdiseasesofinfant7.eosinophiliaLaboratoryDiagnosisLaboratoryDiagnosis1.Byidentifyingtheeggs1.directfecalsmear

2.brine-floatationmethod（飽和鹽水浮聚法）3.Scotchtapetechnique(cellophanetapeimpression)透明膠紙黏貼法

4.Larvalcultivation(鉤蚴培養(yǎng)法)2.Byidentifyingtheadults3.therapeutictestEpidemiologydistributionBasicconditionsinparasiticepidemiologyPatientsandinfectedpersonsSouceofinfectionModeoftransmission(Factorsofprevalence)ForroundwormForhookwormViamouth

WarmerandpoorsanitationInadequatedisposaloffecesUsingnightsoilasfertilizerViaskin

Bare-footwalkingOthers:Oral（A.doudenale)PlacentaMother’smilkParatenichostsSusceptiblepopulation“Hand-to-Mouth”TransmissionretroinfectionthroughanusinhalationofovaForpinwormEpidemiologythereasonforwidedistributionofAscaris

l1.simplelifecycle2.high