《病原生物学（医学微生物学）》课程教学课件（英文）07_Normal microbial flora

Section IIIBacteriologyNormal Microbial Florain Human BodySHIHEZI UNIVERSITY

Section III Bacteriology Normal Microbial Flora in Human Body SHIHEZI UNIVERSITY

KEY TERMS PathogenOpportunistic infectionMicrodysbiosis Translocation Medical Microecology Nosocomial InfectionSHIHEZI UNIVERSITY

KEY TERMS  Pathogen  Opportunistic infection  Microdysbiosis  Translocation  Medical Microecology  Nosocomial Infection SHIHEZI UNIVERSITY

Pathogenic BacteriaNot allbacteriadiseasecause少数细菌总有致病性y bacteria areally pathogenic许多细菌具有潜在致病00性209大多细菌不具有致病性

少 数 少 数 细细菌菌 总 有 致病 总 有 致病 性 性 许多多 细细菌菌 具 有 潜 在 致病 具 有 潜 在 致病 性 性 大 多 大 多 细细菌菌 不 具 有 致病 性 不 具 有 致病 性 Pathogenic Bacteria

Normal Microbial Florathe population of microorganisms thatinhabit the skin and mucous membranes ofhealthy normal personsIt is doubtful whether a normal yiral floraexists in humansSHIHEZIUNIVERSITY

Normal Microbial Flora  the population of microorganisms that inhabit the skin and mucous membranes of healthy normal persons  It is doubtful whether a normal viral flora exists in humans SHIHEZI UNIVERSITY

Normal Microbiota= Normal Flora Normal microbiota Normal microflora Physiological microbiotaSHIHEZI UNIVERSITY

Normal Microbiota= Normal Flora  Normal microbiota  Normal microflora  Physiological microbiota SHIHEZI UNIVERSITY

Normal Microbial Flora Groups Resident floraconsists of relatively fixed types ofmicroorganisms regularly found in a given areaat a given ageIf disturbed tpromptly reestablishes itself Transient floraconsists of nonpathogenic or potentiallypathogenic microorganisms that inhabit theskin or mucous membranes for hours, or daysSHIHEZI UNIVERSITY

Normal Microbial Flora Groups  Resident flora consists of relatively fixed types of microorganisms regularly found in a given area at a given age If disturbed, it promptly reestablishes itself  Transient flora consists of nonpathogenic or potentially pathogenic microorganisms that inhabit the skin or mucous membranes for hours, or days SHIHEZI UNIVERSITY

Transient FloraIt is derived from the environment, does notproduce disease, and does not establish itselfpermanently on the surface Members of the transient flora are generally oflitle significance so long as the normal residentflora remains intact If the resident flora is disturbed, transientmicroorganisms may colonize, proliferate, andproduce diseaseSHIHEZIUNIVERSITY

Transient Flora  It is derived from the environment, does not produce disease, and does not establish itself permanently on the surface  Members of the transient flora are generally of little significance so long as the normal resident flora remains intact  If the resident flora is disturbed, transient microorganisms may colonize, proliferate, and produce disease SHIHEZI UNIVERSITY

Classifications of Normal FloraEnviromentAutochthony (=aboriginesAllochthony (=foreignRelation with host Symbiotic flora Parasitism floraSHIHEZI UNIVERSITY

Classifications of Normal Flora  Enviroment Autochthony (= aborigines) Allochthony (= foreign)  Relation with host Symbiotic flora Parasitism flora SHIHEZI UNIVERSITY

Microecosystem - MicroecologySkinNasopharynx MouthOral cavityThroatTrachea NasopharynxLungsEarEsophagusEyeStomachDuodenumGastrointestineJejunumAscending colon Urinary tructDescendingcolonCecumReproductive tractAppendixRectumSHIHEZI UNIVERSITY

Microecosystem - Microecology  Skin  Mouth  Nasopharynx  Ear  Eye  Gastrointestine  Urinary truct  Reproductive tract  Staphy  E. coli  Pseudomonas  Strepto  Nesseria  Corynebacteria  . .  . . SHIHEZI UNIVERSITY

CyhrawirdMeninges(of brain)CONTACTSinusMicrobes arepicked up onexposed areasMiddle earof the bodyADVERSEBENEFICIALNasalmucosaOUTCOMEEFFECTSPharynxColonizationMicrobes crosswithfloralines of defenseRemovalossand enter sterileTracheaof microbetissuesINVASION→Microbes becomeestablished andgrow in tssuesCarrier state occursPalateDefenses holdINFECTION→Effect of microbespathogen inis injury ordisruptioncheckof tissuesBronchusImmunity/repairDISEASE→MorbidityoccursBronchioleof damageMortalty occursAlveolusSHIHEZIUNIVERSITY

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