蛔虫鞭虫钩虫PPT课件.ppt

复习题？,1.试述保虫宿主与转续宿主的区别。,2.寄生虫为什么能在有免疫力的人体中生存而不被排除？,1,寄生虫病的传播途径包括污染或含有寄生虫的感染期的,土壤水食物节肢动物传播媒介,2,寄生虫感染阶段是指寄生虫的：,感染人体阶段感染保虫宿主阶段感染中间宿主阶段感染中间宿主阶段感染昆虫媒介阶段,3,人体寄生虫病的传染源包括：,仅有病人和带虫者医学节肢动物所有野生动物病人、带虫者、感染的动物,4,关于蛲虫，下列哪项是错误的：,1.生活史简单2.感染率儿童高于成人，城市高于农村3.生活史属间接型4.带虫者和病人是唯一的传染源5.感染方式主要是人群中的间接接触和肛门手口直接感染,5,AscarisLumbricoides,P162,6,AscarisLumbricoides,Ascarislumbricoides,commonsaying“roundwormofman”,isthelargestoftheintestinalnematodesparasitizinghumans.Itisthemostcommonwormfoundinhuman.Itisworldwideindistributionandmostprevalentthroughoutthetropics,sub-tropicsandmoreprevalentinthecountrysidethaninthecity,7,似蚓蛔线虫（蛔虫）,Ascarislumbricoides,一、形态,成虫,活体,2035cm,1531cm,活体,8,AdultwormofA.lumbricoides,9,蛔虫唇瓣扫描电镜图,“品”,10,脱蛋白质膜受精卵,虫卵,11,卵,感染期卵,二生活史,录像,录像,12,侵入肠粘膜的小V、小L,蛔虫幼虫的体内移行：,13,1.Siteofinhabitation:smallintestine2.Infetivestage:embryonatedeggs3.Routeofinfection:bymouth4.Nointermediateandreservoirhosts5.Lifespanoftheadult:about1year,生活史的特点：,14,III.Pathogenesis,Therearetwophasesinascariasis:1.Theblood-lungmigrationphaseofthelarvae:Duringthemigrationthroughthelungs,thelarvaemaycauseapneumonia.Thesymptomsofthepneumoniaarelowfever,cough,blood-tingedsputum,asthma.Largenumbersofwormsmaygiverisetoallergicsymptoms.Eosionophiliaisgenerallypresent.TheseclinicalmanifestationisalsocalledLoefflerssyndrome.,15,2.Theintestinalphaseoftheadults.Thepresenceofafewadultwormsinthelumenofthesmallintestineusuallyproducesnosymptoms,butmaygiverisetovagueabdominalpainsorintermittentcolic,especiallyinchildren.Aheavywormburdencanresultinmalnutrition.Moreseriousmanifestationshavebeenobserved.Wanderingadultsmayblocktheappendicallumenorthecommonbileductandevenperforatetheintestinalwall.Thuscomplicationsofascariasis,suchasintestinalobstruction,appendicitis,biliaryascariasis,perforationoftheintestine,cholecystitis,pancreatitisandperitonitis,etc.,mayoccur,inwhichbiliaryascariasisisthemostcommoncomplication.,录像,16,致病（pathogenesis),录像,1、幼虫致病,2、成虫致病,蛔虫性哮喘,掠夺营养,引起变态反应哮喘,荨麻疹,17,并发症(国内报告8468例),胆道蛔虫症4556例(53.8%)蛔虫性肠梗阻2337例(27.6%)蛔虫性阑尾炎143例蛔虫性胰腺炎17例蛔虫性哮喘1352例蛔虫性肝脓肿33例,18,直接涂片法,四、诊断（diagnosis),改良加藤法,录像,19,五、流行与防治(EndemityandPrevention),Worldwidedistribution,verycommoninChina,especiallyinthecountryside.Factorsfavoringthespreadofthetransmission:1.Simplelifecycle.2.Enormouseggproduction(240,000eggs/day/female).3.Theseeggsarehighlyresistanttoordinarydisinfectants(duetotheascroside).Theeggsmayremainviableforseveralyears.4.Socialcustomsandlivinghabits.5.Disposaloffecesisunsuitable.,流行,20,1.Treatmenttoascariasis:Mebendazole,AlbendazoleandLevamizoleareeffective.2.Sanitarydisposaloffeces.3.Hygienichabitssuchascleaningofhandsbeforemeals.4.Healtheducation.,防治,21,Trichuristrichiura(毛首鞭形线虫),1.Introduction:ThecommonnameofTrichuristrichiuraiswhip-worm(鞭虫),adultsliveincaecum(盲肠)ofhumanandresultintrichuriasis(鞭虫病),22,2.Morphology:,1)Adultsresembleawhip,anteriorwithahair-likelashandposteriorwiththehandle.Mouthcavityisprovidedwithaminutespear2)Male:about4cmlong,posteriorisspirallycoiled.3)Female:about5cmlong,posteriorextremitystraight.,23,4)Egg,Atypicalbarrelshapewithtwopolarplugs(2)Size:50-54mby22-23m(3)Theexternallayeroftheshelloftheeggisyellowbrown(4)Anovumisintheeggwhenitpassedwithstool,24,3.Lifecycle,adults（cecum）,eggs,1T7T/daily,moist、warm35w,infectiveeggs,larvae（smallintestine）,adults（cecum）,migrationdowncecum,Larvaedonotentercirculationsystem！,ingestion,25,26,4.PathologyFeedingontissuefluidandblood;Theslenderanteriorendspenetrateintothegutmucosaandmakelesions;,27,Symptoms:,Symptomsaredeterminedlargelybythewormburden:lightinfectionsareasymptomatic.Heavierinfectionsarecharacterizedby:1)chronicmucousandbloodydiarrhea2)abdominalpains3)hemorrhageandanemia(贫血)orrectalprolapse(直肠脱垂)inheavyinfectionchildren4)Theinfectionmayresultinmalnutritionandgrowthretardation,28,5.Diagnosis,Diagnosisisbasedonsymptomsandthepresenceofeggsinfeces,29,6.Prevalenceandcontrol,Trichuriasisoftenprevailwithascariasis17.38%ofpopulationinfectedwiththisparasiteinChinaThetreatmentandcontrolcanrefertoascariasis,30,十二指肠钩口线虫和美洲板口线虫（钩虫）,(Hookworm),一、形态,成虫,十二指肠钩口线虫,美洲板口线虫,前进,Ancylostomaduodenale,Necatoramericanus,and,31,消化系统的特点：,1、口囊发达2、咽管壁肌肉发达3、头腺、咽管腺分泌抗凝素、乙酰胆碱酯酶。,32,大小,体形,口囊,交合伞,背辐肋,十二指肠钩虫,美洲钩虫,“C”,“S”,两对钩齿,一对板齿,交合刺,尾刺,有,无,圆形,扁圆形,远端分两支，每支再分3小支,基部先分两支，每支再分2小支,:1013x0.6mm,:811x0.40.5mm,:911x0.4mm,:79x0.3mm,前进,33,十二指肠钩虫口囊,美洲钩虫口囊,实物扫描电镜图,34,十二指肠钩虫口囊,美洲钩虫口囊,实物标本,35,十二指肠钩虫交合伞,美洲钩虫交合伞,36,十二指肠钩虫背辐肋,37,美洲钩虫背辐肋,38,十二指肠钩虫背辐肋,美洲钩虫背辐肋,39,钩虫卵,中等大小,椭圆形,无色透明,48个卵细胞,极薄,卵壳与卵细胞间有透明间隙,虫卵,40,二生活史,41,迁延移行,二、生活史,录像,42,侵入皮肤小V、小L,钩蚴的体内移行,录像,43,生活史的特点：,1、寄生部位：2、感染期：3、感染途径：4、感染方式：5、迁延移行：6、丝状蚴特性：7、转续宿主：,小肠,丝状蚴,皮肤、口、胎盘、乳汁等,接触泥土、生食蔬菜和转续宿主肉类、母婴传播等,向温性、向触性,猪、犬、灵猫等,44,录像,1、幼虫致病,2、成虫致病,三、致病（pathogenesis),45,1、边吸血边排血；,2、咬附部位渗血；,3、更换咬附位置，原伤口仍渗血；,4、虫体活动造成组织、血管损伤引起失血。,钩虫引起贫血的原因：,46,四、诊断（diagnosis),直接涂片法,饱和盐水浮聚法,钩蚴培养法,47,五、流行与防治(EndemityandPrevention),1.种植蔬菜与经济作物地区2.用新鲜粪便施肥3.种植时手脚接触泥土的机会多,钩虫病流行的特点与原因,48,五、流行与防治(EndemityandPrevention),录像,1、被钩蚴污染的尿布；,2、睡沙袋、穿“土裤子”；,婴儿感染钩虫的途径：,3、经胎盘感染；,4、经乳汁感染；,49,钩虫病的防治,控制传染源a).治疗钩蚴性皮炎:用左旋咪唑或15%b).治疗钩虫病:首选肠虫清(阿苯达唑),联合用药,如:甲苯咪唑+噻嘧啶,噻嘧啶+左旋咪唑,粪便无害化处理个人防护,噻苯咪唑软膏涂擦.,50,蛔虫的感染阶段是：,受精卵（含一个卵细胞）感染性虫卵未受精卵脱蛋白质膜受精卵,思考题？,51,蛔虫的流行与蛔虫的：,未受精卵有关受精卵与未受精卵都有关受精卵无关受精卵有关,52,蛔虫的主要致病阶段是：,受精卵未受精卵感染性虫卵成虫,53,是非题？,1、钩虫幼虫在体内移行经过肺部引起哮喘是属于幼虫移行症。（）,2、蛲虫卵刚排出即对人体有感染能力（）,3、肠道寄生虫均可通过粪便查到病原体而组织寄生虫则不能。（）,54,思考题？,1、钩虫感染人体的主要方式及途径是：,2.经口感染3.经媒介昆虫叮咬感染4.经胎盘感染5.自体感染,1.经皮肤感染,55,2、俗