全日制义务教育数学课程标准(修改稿)

DHSAcuteCommunicableDiseaseControlProgramD12:\AvianFlu.pptNo.1AVIANINFLUENZA“Thepandemicinfluenzaclockisticking.Wejustdon’tknowwhattimeitis.”LaureneMascola,MD,MPH,FAAPAcuteCommunicableDiseaseControlProgramDHSAcuteCommunicableDiseaseControlProgramD12:\AvianFlu.pptNo.2OUTLINEfBackgroundonInfluenzaAfImpactofinfluenzafPandemicsfAvianinfluenzaAvirusesfHumaninfectionswithavianinfluenzaAvirusessince1997fH5N1Asia2005TimUyeki,MDDHSAcuteCommunicableDiseaseControlProgramD12:\AvianFlu.pptNo.3BACKGROUND:HUMANINFLUENZAfAcutefebrilerespiratoryillness9Symptoms,signsmaydifferbyagefEtiology:infectionwithhumaninfluenzaviruses(infectupperrespiratorytractepithelialcells)92majorsurfaceglycoproteinsƒHemagglutinin,Neuraminadaseƒ8genesegmentscodefor10proteinsfTypesAandBvirusescausesubstantialillnessanddeathamonghumansyearlyTIMUyeki,MDDHSAcuteCommunicableDiseaseControlProgramD12:\AvianFlu.pptNo.4EPIDEMIOLOGYfShortincubationperiod,usually1-4days.fSpreadbyrespiratorydroplets―person-to-person,directcontact,rareaerosolfHighlycontagious;infectiousperiod:9Adults:1daypriortosymptomsthru5dayspostillness9Children:10days9ImmunecompromisedshedvirusforweekstomonthsfVirus1stdetectablejustbeforesymptomonset.Usuallynotdetectableafter5-10daysDHSAcuteCommunicableDiseaseControlProgramD12:\AvianFlu.pptNo.5Surfaceproteins(majorantigens)fHemagglutinin(HA)9Siteofattachmenttohostcells9AntibodytoHAisprotectivefNeuraminadase(NA)9Helpstoreleasevirionsfromcells-oseltamavirworkshere9AntibodytoNAcanhelpmodifydiseaseseverityKEYINFLUENZAVIRALFEATURESNAHATimUyeki,MDDHSAcuteCommunicableDiseaseControlProgramD12:\AvianFlu.pptNo.6IMPACTOFINFLUENZAfSeasonalepidemicsintemperateregions9U.S.,Canada,Europe,Russia,China,Japan,Australia,Brazil,ArgentinafYear-roundactivityintropicalclimates9EquatorialAfrica,SoutheastAsiafU.S.impact9Averageof200,000influenza-relatedhospitalizations/year9Averageof36,000influenza-relateddeaths/yearf3globalpandemicsinthe20thcenturyTimUyeki,MDDHSAcuteCommunicableDiseaseControlProgramD12:\AvianFlu.pptNo.7INFLUENZAPANDEMICS20THCENTURYA(H1N1)A(H2N2)A(H3N2)1918:“SpanishFlu”1957:“AsianFlu”1968:“HongKongFlu”20-40mdeaths675,000USdeaths1-4mdeaths70,000USdeaths1-4mdeaths34,000USdeathsCredit:USNationalMuseumofHealthandMedicineDHSAcuteCommunicableDiseaseControlProgramD12:\AvianFlu.pptNo.8INFLUENZAAVIRUSESINFLUENZAAVIRUSESfSubtypesbasedonsurfaceglycoproteins9Hemagglutinin(HA)andNeuraminidase(NA)9CurrenthumaninfluenzaAvirussubtypes:ƒH1(H1N1,H1N2)ƒH3(H3N2)fCauseepidemicsandpandemicsfInfectmultiplespecies9Humans9Birds(wildbirds,domesticpoultry)9Otheranimals:pigs,horses,dogs,marinemammals(seals,whales))TimUyeki,MDDHSAcuteCommunicableDiseaseControlProgramD12:\AvianFlu.pptNo.9NATURALRESERVOIRFORNEWHUMANNATURALRESERVOIRFORNEWHUMANINFLUENZAAVIRUSSUBTYPES:INFLUENZAAVIRUSSUBTYPES:WATERFOWL(AQUATICDUCKS)WATERFOWL(AQUATICDUCKS)TimUyeki,MDAvianInfluenzaAVirusesH1-H16N1-N9H1-H3HumanInfluenzaAVirusesDHSAcuteCommunicableDiseaseControlProgramD12:\AvianFlu.pptNo.10INFLUENZAAVIRUSESANDANTIGENIC“DRIFT”fAntigenic“drift”:PointmutationsinthehemagglutiningenecauseminorantigenicchangestoHA9Continuousprocess9Immunityagainstonestrainmaybelimited9Vaccinestrainsmustbeupdatedeachyearƒ6-8monthprocessƒTargetedathigh-risk(inactivated);healthy(LAIV)fAntigenic“drift”causesseasonalepidemicsTimUyeki,MDDHSAcuteCommunicableDiseaseControlProgramD12:\AvianFlu.pptNo.11INFLUENZAAVIRUSESANDANTIGENIC“SHIFT”(1)fAntigenic“shift”:EmergenceofanewhumaninfluenzaAvirussubtype(newHAsubtype+/-NA)through:9Geneticreassortment(humanandanimalviruses)9Directanimal(poultry)tohumantransmissionTimUyeki,MDDHSAcuteCommunicableDiseaseControlProgramD12:\AvianFlu.pptNo.12INFLUENZAAVIRUSESANDANTIGENIC“SHIFT”(2)fBecausethereislittleornoimmunitytoanovelvirus,apandemiccanoccurif:9Efficientandsustainedvirustransmissionoccursamonghumans(sustainedperson-to-personspread)fApandemiccanresultin:9Widespreadmorbidityandmortalityworldwide9HighproportionofdeathsamongyoungadultsTimUyeki,MDDHSAcuteCommunicableDiseaseControlProgramD12:\AvianFlu.pptNo.13DEFINITIONOFPANDEMICfIsolationfromhumansofanovelinfluenzaAvirusfLittleornotimmunityinthepopulationfDemonstratedabilityofthevirustoreplicateandcausediseasefEfficientpersontopersontransmissionfMayhaveincreasedmortalitywithhigherproportioninyoungerpersonsDHSAcuteCommunicableDiseaseControlProgramD12:\AvianFlu.pptNo.14WHOALERTPHASESfPhase3:Humaninfection(s)withanewsubtype,butnohuman-to-humanspread,oratmostrareinstancesofspreadtoaclosecontactPANDEMICALERTPERIODWhereweareno:\AvianFlu.pptNo.15DOESAVIANFLU=PANDEMICFLUfNO!fCurrentimpactofhighlypathogenicavianinfluenza(HPAI)virusesonhumanhealthissmallfOnlysince1997,andin2003tillpresentdoweseehumaninfectionsfCurrentA/H5N1virusesarepoorlyadaptedtohumanspecies-rarehumantohumantransmission,raretonomildorasymptomaticinfectionDHSAcuteCommunicableDiseaseControlProgramD12:\AvianFlu.pptNo.16Avian-humanpandemicreassortantvirusAvianvirusHumanvirusAvianreassortantvirusAvianvirusReassortmentinswi