抗生素英文课件精品preventionof infection epidemiologyinfection

PreventionofInfection1Epidemiology InfectionControl ProfessorMarkPallen Overview SourcesofinfectionTransmissionofInfectionPatternsofInfectionOutbreaks EpidemiologicaltypingInfectionControlGeneralPrinciples Hospital CommunityWho swhoHospital acquiredinfectionSyndromesRogues galleryControlofCross InfectionRisksfromHospitalStaffFinalwords foodsalmonellosis campylobacter Humans Animals zoonoses Environment clinicalcasee g measlestuberculosis convalscentcarriere g typhoiddiphtheriahepatitisB symptomlesscarriere g typhoid hepatitis auto infectione g UTIcandidiasis clinicalcasee g rabiespsittacosis carriere g salmonellaleptospirosis vector bornee g malariaLymediseaseplague soile g tetanus watercryptosporidiosis giardia cholera airbornee g legionellosis SourcesofinfectionWheredopatientsgettheirinfectionsfrom inthecommunity SourcesofinfectionWheredopatientsgettheirinfectionsfrom inthehospital TransmissionofInfectionDefinitionsoftermsbyexample Salmonellagastro enteritisReservoirmorecommonlyanimalgutfloralesscommonlyhumancases carriersSourceorVehiclefoodfromaffectedanimalscontaminatedfood TransmissionofInfectionDefinitionsoftermsbyexample S aureuswoundinfectionReservoirHumannose skinSourceorVehicleHandsofhealthcareworkers PatternsofInfectionDefinitions Sporadicrareinfections occurringnowandthen withoutanyparticularpatterne g gasgangrene orStrep pyogeneswoundinfectionsEpidemicAsuddenunexpectedriseinnumberofinfectionscausedbyaparticularpathogenCanrangefromthesmallscalee g afewindividualsuptonationwide e g theBSEepidemicinUK PatternsofInfectionDefinitions Outbreakcommonlyusedtomeanalimitedepidemic e g inahospitalwardPandemicaworld wideepidemice g HIVorinfluenzaEndemicimpliesaconstantsignificantnumberofinfectionsindefinitelye g methicillin resistantS aureusisendemictomanyhospitals e g anoutbreakofsalmonellagastro enteritis No of new cases Day Epidemicinfectionoroutbreak Introductionofpathogen followedby pointsourceoutbreak withabruptstart outbreaksputtersondue tolimitedhuman to humanspread PatternsofInfectionExamples Days e g S aureuswound infectionsinahospital Endemic infection continuouslevelofinfection predominantlyduetohuman to humanspread cross infection PatternsofInfectionExamples Outbreaks Epidemiologicaltyping Whytypeorganisms doyouhaveanoutbreakorjustanincreaseinendemicorsporadicinfection e g S aureusinfectionsinsurgicalunitidentificationofthesourceorextentofoutbreakmayhavelegalimportance e g closedownrestaurantidentificationofmorevirulentstrains TypingmethodsshowwhetherisolatessameordifferentBiochemistry Antibiogram Phagetyping Serotyping Molecularmethods InfectionControlGeneralPrinciples RemovereservoirorsourceofinfectionInterrupttransmissionofinfectionIncreasehostresistancetoinfection InfectionControlinthecommunity Removereservoirs sourcesHuman to humanCasefinding treatmente g TBContacttracingSTDs diphtheria TB meningitisAnimalsCullingofinfectedanimalsE g TB BrucellaEnvironmentCleanwater goodhousing InfectionControlinthecommunity InterrupttransmissionHuman to humanavoidovercrowdingchangesinbehaviour e g safesex isolationofinfectiouscases e g fromschool work Animals EnvironmentFoodhygiene vectorcontrol animalvaccination treatment poop scooping InfectionControlinthecommunity IncreasehostresistanceImproveddietVaccinationChemoprophylaxisMeningitis diphtheria TB Hospital acquiredInfectionwhyworry 10 15 ofpatientswillgetinfectedduringastayinhospitalCosts 1billionperyearinUKAsinglelargeoutbreakcancost10 100KEffectsofnosocomialinfectionIncreasedmortality morbidityProlongedhospitalstayIncreaseddrugsbillIncreasedstaffingcostsDemoralisingforstaff patientsDecreasedpublicconfidenceinhospitals doctors Whyishospital acquiredinfectiondifferentfromcommunity acquiredinfection ManypatientshaveimpairedimmunityAfteranti cancerchemotherapyAftertransplantsExtremesofageManypatientshaveimpairednormalphysiologicaldefencesBreachesinskinImplantedforeignbodies biofilms Impairedphsyiology Peristalsis mucociliaryescalator Manyvulnerablepatientsincloseproximitytoeachotherforprolongedperiodsoftime Whyishospital acquiredinfectiondifferentfromcommunity acquiredinfection Thereisadistincthospitalflora ordinary pathogense gpnemococci E coli S aureus canallcausediseasebothinsideandoutsidehospitalopportunistsonlycauseinfectioninpatientswithimpairedimmunitye gSerratiamarsecens Xanthomonasmaltophilia S epidermidis Corynebacteriumjeikeiummulti resistantbacteriaoverlapwithpreviousgroupsselectedforinadarwinianfashionbyantibioticusageinhospitalsincludeopportunistswhichareinherentlymulti resistant e g Xanthomonasmaltophilia andmulti resistantvarietiesofcommonorganisms e g MRSA gent resistantE coli InfectionControlinhospital Removereservoirs sourcesHuman to humanDischargeinfectiouspatients e g withMRSATreat decontaminatepatientsEnvironmentControlofLegionellaWardhygiene cleaningHospitaldesign InfectionControlinhospital InterrupttransmissionHuman to humanHandwashingWardroutine e g wetmopping AseptictechniqueSterilisation disinfectionIsolationproceduresEnvironmentFoodhygiene pestcontrol theatredesign InfectionControlinhospital IncreasehostresistanceGoodnutrition e g TPNinITU RestorenormalphysiologyasquicklyaspossibleRemovelines cathetersetcVaccinate e g hepatitisB CorrectunderlyingdefectsE gcontroldiabetesStimulateimmunity e g GM CSF InfectionControlwho swhoinhospital InfectionControlDoctorInfectionControlNursesInfectionControlCommitteeFormulatepolicieswastedisposal theatredesign foodhygieneetcSurveillanceofinfectionManagementofoutbreaksStaffeducationPowertoclosewardsandevenwholehospitals Hospital acquiredInfectionSyndromes NosocomialUTI 30 ofhospitalinfectionsUsuallycatheterassociatedAsymptomaticcolonisationcommonTreatmentofclinicalinfectionoftenrequirescatheterremovalBUTonlyunderantibioticcover Hospital acquiredInfectionSyndromes Chestinfection 20 ofnosocomialinfectionsGram negativepneumoniaProblemincriticallyill immunocompromisedpatientsLegionellosisVigilanceisnecessaryforearlydetectionofoutbreaksControlbyraisingthehotwatertempregularcleaning inspectionofwater air coolingsystems Hospital acquiredInfectionSyndromes WoundInfections 20 ofnosocomialinfectionsRatesvarydependingonwhether clean or dirty surgeryBlood streamInfections 30 ofnosocomialinfectionsEspeciallydevice associatedinfectionTreatment removetheforeignbody Hospital acquiredInfectionRoguesgallery Methcillin resistantStaphylococcusaureusMRSAInfectionRequiresvancomycintreatmentColonisationrequiresisolation decontaminationwithmupirocinandbetadineVancomycin resistantenterococciVRE includesE faecalisandE faeciumLowgradepathogensIfalsomulti drugresistanttreatmentcanbedifficultE faeciumbutnotE faecalistreatablewithquinupristin dalfopristin Synercid Hospital acquiredInfectionRogues gallery ClostridiumdifficileCausesAntibiotic associatedcolitisCancauseoutbreaksinhospitalsPatientsshouldbeisolatedGentamicin resistantGNRsRequiretreatmentwithexpensivedrugssuchasamikacinandimipenemPatientsshouldbeisolatedCancauseoutbreakse g ononcologywardsorinITUFungalinfectionAspergillusfumigatusandCandidaalbicanscancausenosocomialoutbreaks ControlofCross Infection Handwashingisparamount evenforConsultants washyourhandsbefore afterexaminingpatients especiallyifyoulookatundressedwoundsAlcoholichandrubsmayprovideaconvenientalternativetosoapandwater especiallywheresinksareinshortsupplyorduringanoutbreak ControlofCross Infection Isolationofinfectiouspatientswheneveryouadmitorassessapatientthink doesthispatientneedtobeisolated generalprecautionsSide roomisolation orcohortnursingorisolationward Hand washingonentry exitUseofapronsandglovesconsultmicrobiologistorinfectioncontrolnurseforadviceinfectioncontrolmanualforisolationprotocolscontainsadviceonmeningitis D V openTB MRSA hepatitis HIV andlotsmorebesides everythingfromLassatolice Prophylaxise g ofcontactsofchickenpox diphtheria meningitis RisksfromHospitalStaff TakeCareOfYourself YourfirstresponsibilityistoyourpatientsnotyourcolleaguesDonotworkifyouhavediarrhoea oraflu likeillness asorethroat orifyoumaybeincubatingaviralillnesssuchasmeasles rubella chickenpox BeConsiderateToLabStaff Don tsendspecimenstothelabwithoutproperpacking leakingand orblood stainedspecimensarenotacceptable Labelhazardousspecimens Summary SourcesofinfectionTransmissionofInfectionPatternsofInfectionOutbreaks EpidemiologicaltypingInfectionControl