传染病学绪论华中科技大学同济医学院

传染病学绪论华中科技大学同济医学院第1页/共70页WhatisanInfectiousDisease?InfectiousDiseases-causedbyhumaninfectionofmicro-organismsandparasitesInfection-theabilityofanorganismtoinvadeandestablishitselfinahostCommunicableInfection-adiseasethatistransmittedfrompersontoanother第2页/共70页WhatisanInfectiousDisease?MicroorganismsBacteriaVirusPrion(盶毒体)FungusProtozoa(原虫)Helminth(蠕虫)Productsfrommicroorganismstoxins第3页/共70页CurrentSituationIncreasinglyseriousthreatsfromCommunicablediseases

Re-emerging:TB(结核),STD,plague(瘟疫),cholera(霍乱)…

Emerging:AIDS,SARS…第4页/共70页第5页/共70页TheIncidenceRateofCommunicableDiseasesinChinaCurrentSituation第6页/共70页TheProportionofDifferentCommunicableDiseasesbyEtiologyinChina,1950’s-2002’sTransmittedbysexorbloodGastrointestinalVector-borneandnaturalendemicRespiratory第7页/共70页LeadingCausesofDeath第8页/共70页第9页/共70页ReemergingInfectiousDiseaseWhy?HumanDemographyandBehaviorTechnologyandIndustryEconomicdevelopmentandLandUseMicrobialAdaptationandChangeBreakdownofPublicHealthMeasuresandDeficienciesinPublicHealth第10页/共70页NaturalEnvironmentDestroy第11页/共70页InfectionandImmunityinfectionimmunityBolusofinfectionxvirulenceimmunityDisease=第12页/共70页ResponsetoInfectioninfectionxdiseaseInnateimmunitynodiseaserecoveryadaptiveimmunityre-infectionnodiseasex第13页/共70页InfectionspectrumPrimaryInfectionRepeatedInfectionMixedInfectionSuperinfectionSecondaryInfection第14页/共70页InfectionPathogeneradicationOvertinfectionClinicalInfectionLatentinfectionPathogeneradicationCarrierPatientColonizationCarrierCovertinfectionSubclinicalinfectionBacteremia/viremiaClinicalOutcomesofInfection②③④⑤①第15页/共70页

Pathogeniceffectivenessofmicro-organismsPathogenecityInvasiveness(colonizationfactor)Virulence(exotoxinandendotoxin)QuantityVariability(HBVmutation)第16页/共70页ImmunityNonspecific

immunitySpecific

immunityNaturalbarrierPhagocytosisHumoralfactorCellularimmunitycomplementcytokinelysozymeHumoralimmunityIgMIgAIgEIgGImmuneResponseinInfectionProcess第17页/共70页CellsoftheImmuneSystemLeukocytes(NotAgspecific)neutrophils(PMN’s)monocyte/macrophageeosinophilbasophilSpecializedcells(Agspecific)B-cells antibodiesT-cells第18页/共70页Tcell’sclassification第19页/共70页Howdoestheimmunesystemwork?MHCclassImoleculepresentinganepitope第20页/共70页InfectionandImmune第21页/共70页InfectionandImmune

(herpessimplex)Initialinfectionbyherpessimplexvirusintheskinisclearedbyaneffectiveimmuneresponse.Butresidualinfectionpersistsinsensoryneurons.Whenthevirusisreactivated,theskinisre-infected.Thiscanberepeatedendlessly.第22页/共70页PathogenesisofInfectiousDisease第23页/共70页DirectInjuryToxinHarmfulImmuneresponseInvasionColonizationOutputPathogenInjuryFeverMetabolismdisorderEndocrinedisturbanceDevelopmentofinfectiousdiseaseInjuryofcellsandtissuesDisorderofpathophysiology第24页/共70页AdhesinsCapsularmaterialProteins(ProteinF,ProteinM)LipotechoicacidsFimbriae&PiliEndotoxinsGramnegativeLPScellwallcomponents(LipidAandCoreSugars)ExotoxinsCanbeproducedbyeitherGramPositiveorGramNegativeOrganismsCellandTissueDamageInduced

byMicro-organismsBacteria第25页/共70页CellandTissueDamageInduced

byMicro-organismsvirusesDirectattachmentandkillingInhibithostcellsynthesis(RNA,DNA,proteins)IntracellularreplicationandlysisSurfacetargetsforhostimmunesystemLocaldirectdamageleadingtosecondarybacterialinfectionsLatentinjury第26页/共70页HarmfulHostResponses

toInfectiousAgentsAutoimmunity:breaktherulesofthe“self-versus-nonself”.Directagainst“self-proteins”Hypersensitivityreactions

typeIorimmediatehypersensitivity(mastcellassociatedIgE)typeIIorcytotoxichypersensitivity(antibody-complementactivationandnaturalkiller)typeIIIorimmune-complex-mediatedhypersensitivitytypeIVordelayed-typehypersensitivity(activatedT,CD8+,Mac)prolongedantigenexposure第27页/共70页EnterovirusPathogeneis第28页/共70页Colonizedherd第29页/共70页EpidemicProcess第30页/共70页EpidemicProcessSourceofinfectionRouteoftransmissionSusceptiblepopulation第31页/共70页Whydopeoplegetsick?Newpathogensorchangesinpathogens(HIV,Nile-likevirus)Changesinenvironmentalconditions(naturalorman-made)HostFactors(Age,gender,ethnicity,immunestatus,Nutritionalstatus,behavior)第32页/共70页

SourceofInfection

PatientCovertinfectedpersonCarrierInfectedanimal第33页/共70页

Othereffectivefactors:

Climate

–Temperature,Humidity…Society

–Sanitation,CulturalBackground,War…第34页/共70页RoutesofTransmissionAir-borne,dropletinfection,dustFomiteborne(污染物):Water,food,fliesDirectcontactofuncleanhandsandfingers,toysVectorborneA)mechanicalB)biologicalBloodandbloodsourceproductsContactwithsoilTransplacental第35页/共70页HIV’sTransmissionRoutes第36页/共70页SusceptiblePopulationAgroupofpeopleatincreasedriskforinfectionandillnessfromapathogen,oftencausedbyadecreaseintheeffectivenessoftheperson’simmunesystem.第37页/共70页ChainofTransmissionPortalofexitPortalofentryAgentSusceptibleHostModeoftransmissionReservoirPersontopersontransmission第38页/共70页AgentHostEnvironment

AgeSex

GenotypeBehaviour

Nutritionalstatus

Healthstatus

InfectivityPathogenicityVirulenceImmunogenicityAntigenicstabilitySurvival

WeatherHousing

Geography

OccupationalsettingAirquality

FoodFactorsInfluencingDiseaseTransmission第39页/共70页DistributionduetoSocioeconomicHepatitisATyphoidfeverHelicobacterpyloriOtherbacterialdiarrheasTuberculosis第40页/共70页CharacteristicsofInfectiousDiseases第41页/共70页PathogenInfectivity:isolationofpatientsEpidemiologicfeature:continuewithnextslidePost-infectionimmunityBasicfeatures第42页/共70页

LevelofEpidemicSporadiclevel

-occasionalcasesoccurringatirregularintervals

Endemiclevel

-persistentoccurrencewithalowtomoderatelevel

Hyperendemiclevel

-persistentlyhighlevelofoccurrenceEpidemicoroutbreak

-occurrenceclearlyinexcessoftheexpectedlevelforagiventimeperiodPandemic

-epidemicspreadoverseveralcountriesorcontinents,affectingalargenumberofpeople第43页/共70页ClinicalPhageIncubationperiod(潜伏期)Prodromalperiod(前驱期)Manifestationperiod(症状期)Recoveryphase(恢复期)Relapse(复发):fullyrecoveranddiseasere-appearesRecrudescence(再燃):notfullyrecoveredandgotworserSequela(后遗症):functionallynotfullyrecovered第44页/共70页1.Effervescence(increasing)2.Fastigium(peaking)3.Defervescence(decreasing)SymptomsandsignsFeverProcess第45页/共70页SymptomsandsignsFevertypesSustainedFeverRemittentFeverIntermittentFever(septicfever)RelapsingFever(UndulantFever)SaddleTypeFeverIrregularFever第46页/共70页FevertypeSustainedFeverRemittentFeverIntermittentFever(septicfever)UndulantFeverRelapsingFeverIrregularFever第47页/共70页SkinEruptionMacule(班疹)Maculo-papule(班丘疹)Roseola(玫瑰疹)第48页/共70页SkinEruptionPetechiae(出血疹)EcchymosisHerpes第49页/共70页TheTimeRashAppears

Day1Rubella(风疹)

Day2

ScarletFever(猩红热)

Day3SmallPox(天花)

Day5TyphusFever(班疹伤寒)Day6

Typhoid(伤寒)第50页/共70页OtherSymptomsConjunctivacongestedEnlargementoflymphnodesToxemicsymptomsBleedingComaMononuclear-phagocytesystemresponseSpleno-hepatomegaly第51页/共70页Diagnosis

Epidemiologyvitalandsignificantindiagnosis

ClinicalManifestationsuchasroserash,splenohepatomegaly,gastrocnemiustenderness

LaboratoryTestmainmeansfordiagnosis第52页/共70页LaboratoryTest

LightMicroscopy

H&EstainedsectionsSpecialStains:Gram,AcidFast,Giemsa

Culture

Bacterial,Mycobacterial,Fungal,Viral

ImmuneTest

SerologicStudies–ELISAImmunoperoxidaseStainsDirectFluorescentAntibodies

PolymeraseChainReaction第53页/共70页TreatmentGeneralandsupportingtreatmentHeteropathy(对症治疗)PathogenicandspecifictreatmentRehabilitationtherapyTraditionalChineseMedicineandacupuncturetreatment第54页/共70页AntibioticTherapyProperdosePropertimeintervalProperrouteofadministration(oral,parenteral)Combinationantibiotictherapy第55页/共70页Themainclassesofantibiotics

AminoglycosidesCephalosporinsFluoroquinolonesMacrolidesPenicillinsTetracyclines第56页/共70页AntibioticResistance第57页/共70页AntiviralTherapyInterferonNucleosideAnaloguesHighActiveAnti-RetroviralTherapy,HAARTTreatHIV,HBV,HCV…InterferonLamivudine第58页/共70页AntiparasiticDrugs

Antimalarial(抗疟药)

•

CHLOROQUINE(氯喹)

AntiprotozoalDrugs(抗原虫药)

Amebiasis(阿米巴病)andTrichomonas(毛滴虫属)

•

METRONIDAZOLE(甲硝唑)

Fluke(吸虫)andTapeworm(绦虫)Infections

Schistosomiasis(血吸虫病)

•

PRAZIQUANTEL(吡喹酮)Filariasis(丝虫病)

•

diethylcarbamazine(乙胺嗪)IntestinalRoundworms(Ascaris),(线虫,蛔虫)Enterobius(Pinworm)(蛲虫)andHookworm(钩虫)

•

Albendazole(丙硫咪唑)第59页/共70页ProphylaxisSanitationwaterandwastetreatmentpersonalhygieneVaccinationprobablythebestwaytopreventcommunicablediseasesHealthylivingpracticesafesexavoiddrugsAntibioticsandotherdrugs第60页/共70页Prophylaxis第61页/共70页LawofthepeoplesRepublicofChinaonPreventionandTreatmentofInfectionsDiseases

Article3TheinfectiousdiseasesgovernedbythisLawaredividedintoClassesA，BandC.InfectiousdiseasesunderClassAareplagueandcholera.第62页/共70页LawofthepeoplesRepublicofChinaonPreventionandTreatmentofInfectionsDiseasesInfectiousdiseasesunderClassBareinfectiousSARS，AIDS，viralhepatitis,poliomyelitis，highlypathogenicavianinfluenza，measles，epidemichemorrhagicfever，rabiesepidemicencephalitisB，denguefever，anthrax，bacillaryandamebicdysentery，pulmonarytuberculosis，typhoidandparatyphoid，epidemiccerebrospinalmeningitis，pertussis，diphtheria，tetanusinfantum，scarletfever，brucellosis，gonorrhoea，syphilis，leptospirosis，schistosomiasisandmalaria.第63页/共70页LawofthepeoplesRepublicofChinaonPreventionandTreatmentofInfectionsDiseasesInfectiousdiseasesunderClassCareinfluenza，epidemicparotitis，rubella，acutehemorrhagicconjunctivitis，leprosyepidemicandendemictyphus，kala-azar，echinococcosis，filariasis，andinfectiousdiarrheaotherthancholera，bacillaryandamebicdysentery，typhoidandparatyphoid.第64页/共70页LawofthepeoplesRepublicofChinaonPreventionandTreatmentofInfectionsDiseasesArticle30Whendiseasepreventionandcontrolinstitutions，medicalagencies，bloodcollectorsandsuppliesortheirstaffmembersondutyfindtheepidemicsituationofinfectiousdiseasesorthethisLawortheoutbreakandprevalenceofotherinfectiousdiseasesortheinfectiousdiseasesthecausesforthesuddenoutbreakofwhichareuncertain，theyshallreportinadherencetotheprincipleofterrito