哈尔滨医科大医学微生物PPT课件 第37章 肝炎病毒

MedicalMicrobiologyDepartmentofMicrobiology,HMU第37章肝炎病毒Hepatitisviruses微生物学教研室凌虹第二篇致病性细菌教学大纲掌握内容肝炎病毒的种类乙型肝炎病毒形态结构、致病性、预防原则熟悉内容丁型肝炎病毒结构特征及致病特点戊型肝炎病毒传播途径及致病特点问题肝炎病毒有哪些？甲型肝炎病毒的传播方式、致病特点和预防原则简述乙型肝炎病毒的生物学性状、抗原抗体组成及检出的意义、传播方式、致病特点及预防原则丙型肝炎病毒的生物学特点和致病特点丁型肝炎病毒（HDV）的概念简述戊型肝炎病毒传播方式和致病特点肝炎病毒（Hepatitisvirus）以侵害肝脏为主引起病毒性肝炎的病毒种类：甲型肝炎病毒（HAV）、乙型肝炎病毒（HBV）、丙型肝炎病毒（HCV）、丁型肝炎病毒（HDV）、戊型肝炎病毒（HEV）、GBV-C/HGV、TTV其他病毒黄热病毒、CMV、EBV、风疹病毒等ViralHepatitis-HistoricalPerspectivesA“Infectious”“Serum”ViralhepatitisEntericallytransmittedParenterallytransmittedF,G,TTV?otherENANBBDCHepatitisAvirus1973年Feinstone应用免疫电镜技术从急性肝炎患者粪便发现生物学性状与肠道病毒一致1982年国际病毒命名委员会将它分类为小核糖核酸病毒科肠道病毒属72型Anti-HAVPrevalenceHighIntermediateLowVeryLowGeographicDistributionofHAVinfection生物学性状HAV为球形颗粒，直径27～32nm，无包膜。基因组为线状单正链RNA由VP1～4四种多肽组成VP1是主要衣壳蛋白和中和抗原，能中和所有HAV细胞培养：HAV可用猴肾、人胚肾细胞等进行增殖和传代，但不引起CPE易感动物有黑猩猩、南美洲猴、猕猴等接种后可出现急性肝炎抵抗力：较强对乙醚、酸、热（60oC）稳定。高压、紫外、煮沸等可灭活流行病学传染源患者和隐性感染者传播方式：粪－口途径污染食物、水源、海产品引起暴发或散发流行隐性感染率高成人HAV抗体阳性率高达70%—90%致病性非溶细胞型病毒，不直接杀伤细胞病毒复制量与症状严重程度不一致，故认为免疫应答参与损伤过程病后期粪便可检出sIgA抗体无慢性病例典型的甲肝是自限过程，大约三个月甲型肝炎血清学变化过程SourcesofHAVInfection

1983-93PercentageofCasesSource:CDC,ViralHepatitisSurveillanceProgramYearPersonalcontactDaycarecenterForeigntravelOutbreakDruguse40302010019831984198519861987198819891990199119921993ConcentrationofHAVinVariousBodyFluidsSource: ViralHepatitisandLiverDisease1984;9-22 JInfectDis1989;160:887-890FecesSerumSalivaUrine1001021041061081010InfectiousDosespermlAge-specificIncidenceofHepatitisA1983-93Source:CDC,NationalNotifiableDiseasesSurveillanceSystemYearReportedCases(per100,000)198319841985198619871988198919901991199219930510152025

5-14years

15-24years

25-39years

0-4years

40+yearsEndemicityDiseaseRatePeakAgeofInfectionTransmissionPatternsHighLowtoHighEarlychildhoodPersontoperson;outbreaksuncommonModerateHighLatechildhood/youngadultsPersontoperson;foodandwaterborneoutbreaksLowLowYoungadultsPersontoperson;foodandwaterborneoutbreaksVerylowVerylowAdultsTravelers;outbreaksuncommonGlobalPatternsofHepatitisAVirusTransmission诊断（LaboratoryDiagnosis）AcuteinfectionisdiagnosedbythedetectionofHAV-IgMinserumbyEIAPastInfectioni.e.immunityisdeterminedbythedetectionofHAV-IgGbyEIA防治原则加强食品卫生管理，水源减毒疫苗株H2株和L1株已投放市场基因工程疫苗也正在研究之中应急预防可用丙种球蛋白Manycasesoccurincommunity-wideoutbreaksnoriskfactoridentifiedformostcaseshighestattackratesin5-14yearoldschildrenserveasreservoirofinfectionPersonsatincreasedriskofinfectiontravelershomosexualmeninjectingdrugusers

HepatitisAVaccinationStrategiesEpidemiologicConsiderations

Pre-exposuretravelerstointermediateandhighHAV-endemicregionsPost-exposure(within14days)RoutinehouseholdandotherintimatecontactsSelectedsituationsinstitutions(e.g.,daycarecenters)commonsourceexposure(e.g.,foodpreparedbyinfectedfoodhandler)HepatitisAPrevention-ImmuneGlobulinGroupAgeNo.DosesEL.U.*(ml)Schedule(months)Childrenandadolescents2-18years3360(0.5)0,1,6-12Adults>18years21,440(1.0)0,6-12DosesHAVRIXâ*ELISAunitsRecommendedDoses&SchedulesofHAVVaccinationHapatitisBVirus1963年Blumberg在多次输血的血友病患者中发现澳抗，1968年确与血清型肝炎高度相关，1970年Dane在电镜下看到具有传染性的42nm病毒颗粒HBV在亚洲广泛流行，在中国约10%人口携带该病毒，全球约3.5亿1983年将HBV及与其分子结构、生物学特性相似的土拨鼠肝炎病毒(woodchuckhepatitisvirus,WHV)、地松鼠肝炎病毒(groundsquirrelhepatitisvirus,GSHV)及鸭肝炎病毒(duckhepatitsvirus,DHV)归纳起来独立命名为嗜肝病毒科（Hepadnaviridae）HBsAgPrevalence³8%-High

2-7%-Intermediate

<2%-LowGeographicDistributionofChronicHBVInfection形态与结构电镜检查血清标本可见小球形颗粒（22nm）、管形颗粒（22nmx50—700nm）、大球形颗粒（42nm）完整的HBV颗粒亦称Dane颗粒，颗粒直径为42nm具有双层衣壳结构。外壳相当于包膜，由脂质双层和乙肝表面抗原（HBsAg）、多聚人血清白蛋白受体（PHSA-r）和前S抗原（Pre-S）组成。内部有28nm的核心，表面相当于内衣壳，含有乙型肝炎核心抗原（HBcAg）和乙型肝炎e抗原（HBeAg）。内部有HBV的DNA和DNA多聚酶HBV基因组DNA是由3.2KB的长链L（-）和短链S（+）（约为L链的50%至85%长）组成的不完全双链环状DNA，长链载有病毒蛋白质的全部密码，有4个开放读码框架(ORF)，分别称为S、C、P和X区HBV复制周期HBVReplicationHBV2.4KB3.5KBProvirusRTReplicateNuclear2.1KB抗原组成HBV表面抗原（HBsAg）是机体受HBV感染的标志226AA，由S基因编码HBsAg有1个共同抗原决定簇a和2组互相排斥的亚型抗原决定簇d/y和w/r4种亚型：adr、adw、ayr、ayw我国内地和沿海各省汉族主要为adr型，欧美为adw抗HBs能与HBV表面结合，使其失去感染性，具有保护作用HBV核心抗原（HBcAg）在肝细胞核中才能检出分子量22KD，由C基因编码，病毒内衣壳蛋白一般方法在血中检测不到抗HBc无中和作用检出高效价抗HBc，特别是抗HBcIgM表示HBV再肝内处于增殖状态HBVe抗原（HBeAg）由PreC和C基因共同编码，15KDHBcAg在细胞经蛋白酶降解形成HBV复制及血清有传染性的标志抗Hbe对HBV感染有一定保护作用前S抗原（Pre-SAg）前S2蛋白S+PreS2编码，226+55=281AA前S1蛋白S+PreS2+PreS1编码，226+55+119=400AA与HBsAg、HBVDNA检出相同，都说明病毒在复制Pre-S2抗原和人肝细胞表面都具有PHSA受体，通过PHSAr搭桥，HBV病毒易吸附于肝细胞表面部分解释为什么HBV具有嗜肝细胞性抗前S1和抗前S2抗体具有中和HBV作用，有保护作用易感动物和细胞培养：只有黑猩猩对HBV易感，体外细胞培养尚未成功抵抗力：强对低温、干燥、UV、醚、氯仿、酚等均有抵抗性高压蒸汽灭菌、0.5%过氧乙酸、5%次氯酸钠、3%漂白粉液、0.2%新洁尔灭均可灭活病毒，但处理时间要稍长

Incubationperiod: Average60-90days

Range45-180daysClinicalillness(jaundice): <5yrs,<10%

5yrs,30%-50%Acutecase-fatalityrate: 0.5%-1%Chronicinfection: <5yrs,30%-90%

5yrs,2%-10%

Prematuremortalityfrom

chronicliverdisease: 15%-25%

HepatitisB-ClinicalFeaturesSpectrumofChronicHepatitisBDiseasesChronicPersistentHepatitis-asymptomaticChronicActiveHepatitis-symptomaticexacerbationsofhepatitisCirrhosisofLiverHepatocellularCarcinomaHigh(>8%):45%ofglobalpopulationlifetimeriskofinfection>60%earlychildhoodinfectionscommonIntermediate(2%-7%):43%ofglobalpopulationlifetimeriskofinfection20%-60%infectionsoccurinallagegroupsLow(<2%):12%ofglobalpopulationlifetimeriskofinfection<20%mostinfectionsoccurinadultriskgroupsGlobalPatternsofChronicHBVInfection

HighModerateLow/NTbloodsemenurineserumvaginalfluidfeceswoundexudatessalivasweattearsbreastmilkConcentrationofHepatitisBVirusinVariousBodyFluids

ModesofTransmissionofHBVSexualsexualandhomosexualsareparticularatriskParenteral

Intravenousdrugabuse(IVDA),HealthWorkersareatincreasedriskPerinatalMotherswhoareHBeAgpositivearemuchmorelikelytotransmittotheiroffspringthanthosewhoarenotPerinataltransmissionisthemainmeansoftransmissioninhighprevalencepopulations传染源：急、慢性乙肝患者及无症状携带者传播途径：非胃肠道途径血液、血制品传播输血、丙种球蛋白医源性传播：注射（吸毒）、手术、采血、针刺、拨牙、内窥镜检查、纹身等接触传播：公共卫生洁具、剃刀、吸血昆虫母婴传播宫内感染相对少（<10%）母亲HBeAg阳性婴儿感染机会大（90%）HBeAg阴性、抗HBe阳性婴儿感染机率小（10%—15%）*Includessexualcontactwithacutecases,carriers,andmultiplepartners.Source:CDCSentinelCountiesStudyofViralHepatitisHeterosexual*(41%)HomosexualActivity(9%)HouseholdContact(2%)HealthCareEmployment(1%)Other(1%)Unknown(31%)InjectingDrugUse(15%)RiskfactorsforAcuteHepatitisB

1992-1993USASource:CDCViralHepatitisSurveillanceProgram0-1415-1920-2930-3940+0510152025RateofReportedHepatitisBbyAge

GroupUSA1990AgeGroup(years)Rate(/100,000)ExposureInfectionDeath1%FulminanthepatitisRecovery90%-95%ImmuneAsymptomaticCarrierPersistentInfectionChromichepatitisChronicactivehepatitisCirrhosisHepatocellularcarcinoma致病机理尚未完全明了HBV不直接损害肝细胞，通过宿主的免疫应答引起肝细胞的损伤和破坏细胞免疫损伤细胞免疫强弱与临床过程轻重与转归密切相关免疫力过强可出现重症肝炎，过低则是慢性肝炎体液免疫损伤：不十分重要先天性无丙种球蛋白血症患者乙肝仍表现为典型的肝炎病变抗原抗体复合物超敏反应，造成了肝外症状表现自身免疫损伤HBV感染后，肝细胞自身表面抗原—肝特异性脂蛋白抗原（Liverspecificprotein,LSP）暴露HBV与原发性肝细胞癌乙肝患者原发性肝癌发生率比对照高原发性肝癌患者有HBV感染标志者比自然人群多HBV感染者比阴性者发生原发性肝癌的危险性高217倍WHV可诱导土拨鼠肝硬化及原发性肝癌新生土拨鼠感染WHV三年后100%发生肝癌未感染鼠则无一只发生肝癌肝癌细胞DNA整合有HBV-DNA免疫性体液免疫HBV的中和抗体抗HBs抗Pre-S2细胞免疫CTL是清除细胞内病毒的主要机制细胞免疫处于较低水平则易转为慢性微生物学检查法病毒核酸的检测斑点杂交法，PCR，极敏感的方法，临床常规对血清病毒DNA浓度可做动态监测HBV抗原、抗体的检测最敏感方法是RIA、ELISA检测项目HBsAg和抗-HBsHBeAg和抗-Hbe抗-HBcIgM和抗HBc-IgGSymptomsHBeAganti-HBeTotalanti-HBcIgManti-HBcanti-HBsHBsAg0481216202428323652100TypicalSerologicCourseWeeksafterExposureTitreAcuteHepatitisBVirusInfectionwithRecoveryIgManti-HBcTotalanti-HBcHBsAgAcute(6months)HBeAgChronic(Years)anti-HBe0481216202428323652YearsWeeksafterExposureTitreProgressiontoChronicHepatitisBVirusInfectionTypicalSerologicCourseHBsA：表示机体感染了HBV急性乙型肝炎潜伏期和急性期（70%）HBV所致的慢性肝病如慢性乙型肝炎、肝硬化和原发性肝炎无症状HBsAg携带者抗HBs机体曾感染过HBV，并获得对HBV的免疫力HBcAg：常规方法难以检出，临床不做抗HBc抗HBcIgM出现于急性乙型肝炎急性期抗HBcIgG阳性表示过去感染过HBV，少数也可能仍有HBV感染HBeAg：体内HBV复制和血液传染性强急性乙肝HBeAg呈短暂阳性，如持续阳性提示转为慢性，预后不良孕妇HBeAg阳性，新生儿感染率高抗Hbe见于急性乙肝的恢复期，可持续较长时间机体获得一定免疫力Pre-S1、Pre-S2和PHSA受体HBV新感染的标志，检出表示HBV正在复制抗Pre-S1、抗Pre-S2中和病毒出现于急性乙肝恢复早期消失较快ExamplesofSerologyTest预防原则要采取切断传播途径为主的综合性措施自动免疫：HBsAg疫苗（血源或重组）被动免疫：乙肝免疫球蛋白(HBIg)。接种者:医务人员或实验室工作人员HBsAg、HBeAg阳性母亲的新生儿发现已误用HBsAg阳性的血液或血制品者与HBsAg、HBeAg阳性者有密切性接触者

EliminationofHBVTransmissionPreventperinatalHBVtransmissionRoutinevaccinationallinfantschildreninhigh-riskgroupsadolescentsallunvaccinatedchildrenat11-12yearsadultsinhigh-riskgroupsVaccinelicensedHBsAgscreeningofpregnantwomenrecommendedInfantimmunizationrecommendedAdolescentimmunizationrecommendedDeclineamonghomosexualmen&HCWsDeclineamonginjectingdrugusers80706050403020100787980818283848586878889909192939495YearCasesper100,000PopulationEstimatedIncidenceofAcuteHepatitisB,USA1978-1995HepatitisCvirus1978年WHO将非甲非乙型肝炎病毒按传播途径分为肠道传播的非甲非乙型病毒和肠道外传播的非甲非乙型肝炎病毒1989年进一步将前者命名为戊型肝炎病毒（HEV），将后者命名为丙型肝炎病毒（HCV）目前拟将HCV和庚型肝炎病毒（HGV）列入黄病毒科（Flavivurus）Hepacivirus属生物学性状HCV属于黄病毒科，电镜照片不清晰，似球形，直径55～65nm，有脂蛋白包膜，包膜上有短突起。核酸为+ssRNA，9.4Kb由于不能培养，故尚不能进行血清分型据基因序列同源性，分为I—VI六个基因型。中国和亚洲流行多Ⅱ型，欧美为I型细胞培养未成功黑猩猩是唯一易感动物

hypervariableregioncapsidenvelopeproteinprotease/helicaseRNApolymerasec225’coreE1E2NS2NS333cNS4c-100NS53’HepatitisCVirusGenome

HCV基因结构

HepatitisC-ClinicalFeatures潜伏期平均6-7周（2-26周）急性表现（黄疸）轻微(<20%)急性期死亡率低慢性感染率 75%-85%慢性肝炎 70%肝硬化 10%-20%慢性肝脏疾病导致死亡 1%-5%ChronicHepatitisCInfectionThespectrumofchronichepatitisCinfectionisessentiallythesameaschronichepatitisBinfectionAllthemanifestationsofchronichepatitisBinfectionmaybeseen,albeitwithalowerfrequencyi.e.chronicpersistenthepatitis,chronicactivehepatitis,cirrhosis,andhepatocellularcarcinoma病理HCV不直接杀伤细胞病理免疫和细胞凋亡是造成伤害原因TransmissionofHCVPercutaneous

IntravenousdrugabuseTransfusion,transplantTherapeutic(contaminatedequipment,unsafeinjectionpractices)PermucosalPerinatalSexualSourcesofInfectionfor

PersonswithHepatitisCSexual15%Other*5%Unknown10%Injectingdruguse60%Transfusion10%(beforescreening)*Nosocomial;Health-carework;PerinatalSource:CentersforDiseaseControlandPreventionSource:SentinelCounties,CDCHCVPrevalencebySelectedGroups,USAHemophiliaInjectingdrugusersSurgeons,PSWsHemodialysis

AveragePercentAnti-HCVPositiveGenpopulationadultsMilitarypersonnelSTDclientsPregnantwomenPrevalenceofHCVInfectionby

Age&Gender,1988-1994USAMalesFemalesSource:CDC,NHANESIIITotalPerinatalTransmissionofHCVTransmissiononlyfromwomenHCV-RNApositiveatdeliveryAveragerateofinfection6%Higher(17%)ifwomanco-infectedwithHIVNoassociationwithDeliverymethodBreastfeedingInfectedinfantsdowellSeverehepatitisisrareHouseholdTransmissionofHCVRarebutnotabsentCouldoccurthroughpercutaneous/mucosalexposurestobloodTheoreticallythroughsharingofcontaminatedpersonalarticles(razors,toothbrushes)ContaminatedequipmentusedforhometherapiesInjections*Folkremedies*ReportedinU.S.SerologicPatternofAcuteHCVInfectionwithRecoverySymptoms+/-TimeafterExposureTiteranti-HCVALTNormal01234561234YearsMonthsHCVRNA

SerologicPatternofChronicHCVInfectionwithProgressionInfectionSymptoms+/-TimeafterExposureTiteranti-HCVALTNormal01234561234YearsMonthsHCVRNA

LaboratoryDiagnosisHCVantibody-generallyusedtodiagnosehepatitisCinfection.Notusefulintheacutephaseasittakesatleast4weeksafterinfectionbeforeantibodyappears.HCV-RNA

-varioustechniquesareavailablee.g.PCRandbranchedDNA.MaybeusedtodiagnoseHCVinfectionintheacutephase.However,itsmainuseisinmonitoringtheresponsetoantiviraltherapy.HCV-antigen-anEIAforHCVantigenisavailable.ItisusedinthesamecapacityasHCV-RNAtestsbutismucheasiertocarryout.HCVInfectionTestingAlgorithm

forDiagnosisofAsymptomaticPersonsEIAforAnti-HCVNegative(non-reactive)STOPPositive(repeatreactive)ORRIBAforAnti-HCVRT-PCRforHCVRNANegativeSTOPAdditionalLaboratoryEvaluation(e.g.PCR,ALT)NegativePositiveIndeterminateMedicalEvaluationPositiveNegativePCR,NormalALTPositivePCR,AbnormalALTSource:MMWR1998;47(No.RR19)

RoutineHCVTestingNotRecommended(UnlessRiskFactorIdentified)

Health-care,emergencymedical,andpublicsafetyworkersPregnantwomenHousehold(non-sexual)contactsofHCV-positivepersonsScreeningofblood,organ,tissuedonorsHigh-riskbehaviormodificationBloodandbodyfluidprecautions

PreventionofHepatitisCEstimatedIncidenceofAcuteHCVInfection,1960-1999USADeclineintransfusionrecipientsDeclineininjectiondrugusersSource:Hepatology2000;31:777-82

Hepatology1997;26:62S-65SPosttransfusionHepatitisC

AllvolunteerdonorsHBsAgDonorScreeningforHIVRiskFactorsAnti-HIVALT/Anti-HBcAnti-HCVImprovedHCVTestsAdaptedfromHJAlterandToblerandBusch,Clin

Chem1997TreatmentInterferon-maybeconsideredforpatientswithchronicactivehepatitis.Theresponserateisaround50%but50%ofresponderswillrelapseuponwithdrawaloftreatment.Ribavirin

-thereislessexperiencewithribavirinthaninterferon.However,recentstudiessuggestthatacombinationofinterferonandribavirinismoreeffectivethaninterferonalone.HepatitisDvirusδ肝炎病毒（Hepatitisδvirus）从HBV感染者中发现的HDVPrevalenceHighIntermediateLowVeryLowNoDataTaiwanPacificIslandsGeographicDistributionofHDVInfection生物学性状35～37nm，球形颗粒环状单股负链RNA和HDAg（即δ抗原）1.7Kb表面为HBV包膜蛋白（HBsAg）HBsAgRNAdantigenHDV为缺陷病毒不能独立进行复制，必须在HBV或其它嗜肝DNA病毒辅助才能增殖敏感动物黑猩猩，土拨鼠和北京鸭等HepatitisD-ClinicalFeaturesCoinfectionsevereacutediseaselowriskofchronicinfectionSuperinfectionusuallydevelopchronicHDVinfectionhighriskofseverechronicliverdiseasemaypresentasanacutehepatitis

HDVTransmissionPercutanousexposuresinjectingdrugusePermucosalexposuressexcontact免疫性抗HDV不能清除病毒，为诊断指标HDVIgM和IgG持续存在，提示为HDV慢性感染TimeafterExposureTiteranti-HBsSymptomsALTElevatedTotalanti-HDVIgManti-HDVHDVRNAHBsAgSerologicalCourseofAcuteHDVinfectionTimeafterExposureTiterJaundiceSymptomsALTTotalanti-HDVIgManti-HDVHDVRNAHBsAgSerologicalCourseofHDVsuperinfection微生物学检查法血清学方法ELISA检查HDAg或抗HDVHDAg在急性期可阳性，检出率低慢性感染检不到核酸分子杂交法HBV-HDVCoinfectionPreorpostexposureprophylaxistopreventHBVinfection.HBV-HDVSuperinfectionEducationtoreduceriskbehaviorsamongpersonswithchronicHBVinfection.

HepatitisD-PreventionHepatitisEvirus，HEV戊型肝炎病毒经肠道传播的非甲非乙型肝炎病毒疾病：戊型肝炎Geograp