Unit 9 Human Biology-Lesson 3 Epidemics Explained 课件（内嵌视频）2026-2027学年高中英语北师大版选择性必修第三册

Unit9HumanBiologyLesson3EpidemicsExplained2Whatisthevideoabout?DoyouremembertheoutbreakofCOVID-19?DoyoustillremembertheoutbreakofCOVID-19

?When?Where?Effects?Epidemic(传染病)covid-19Whatdoyouknowaboutepidemics?·Discussingroups.Tick(√)thestatementsthatyouthinkarecorrect.□Anepidemicistherapidspreadofaninfectiousdisease.□Anepidemiccanaffectalargenumberofpeopleinagivenpopulation.□Anepidemiccanoccurwithinashortperiodoftime,usuallytwoweeksorless.□Anepidemicmayspreadtoseveralcountriesorcontinents.□Somecommonviruses,suchasthecommoncold,arenotepidemics.□Anewepidemiccanbeadifferentvariationofavirusthatpeoplecaughtinthepast.Readtoknowmoreaboutepidemics.·1.Skimandmatchmainideaswitheachpart.Part1(Para.1)A.Solutionstofightagainstepidemic.Part2(Para.2)Part3(Para.3-8)Part4(Para.9)B.Thecriteria(标准)ofjudginganepidemic.C.Theexamplesofepidemicsinhistory.D.Thedefinition&causesofanepidemic.·

ScanPara1andfindthedefinition&causesofanepidemic.Anepidemicisthenamegiventoaninfectiousdiseasethatrapidlyspreadstoalargenumberofpeoplewithinashortperiodoftimeusuallytwoweeksorless.EpidemicshavebeenhappeningforaslongastherehavebeenpeoplelivingonEarth.Theycanbecausedbyseveraldifferentfactors,suchasavirusbeingcarriedintoanarea,orchangesinthewaypeoplelive,likemorepeoplelivinginanarea,whichincreasesthechancesofthemcomingintocontactwithabacteriaorvirus.·ScanPara2.findthecriteriaofjudginganepidemic.Eachdiseasecanonlyofficiallybeclassifiedasanepidemiconceacertainnumberofdeathshaveoccurredfromthedisease.Thenumberofdeathsisdifferentforeverydisease.Soaveryrarediseasewillhavealowbaselineandjustafewcasesofitinoneplacewillbeclassifiedasanepidemic,asopposedtomorecommondiseases,suchastheflu,thathaveahigherbaseline.Thecommoncoldisawidespreadvirusthataffectsmillionsofpeople,butitisnotseenasbeingaseriousenoughconditiontodeservetheclassificationofepidemic.·ScanPara(1-2)anddiscussthequestion.Whatarethemainfeaturesofanepidemic?Itisinfectious;Itspreadsrapidly;Causeacertainnumberofdeaths;Occurwithinashortperiodoftime;Alargenumberofpeopleareinfected;·Withrecentpressreportsdrawingparallelsbetweenbirdfluandkillerepidemicsofthepast,JimSmithlooksatthesometimesdepressinghistoryofepidemicsforcluesabouthowwecancreateamorepositivefuturewithoutepidemics.ScanPara3andUnderstand.birdflu1918SpanishFluTheBlackDeathSARSEbolaVirusDisease(EVD)2.Circlealltheepidemicsmentioned.TheEpedimicinRomanEmpire·Sincebirdflu

firstappearedin1997,ithastakenmorethanahundredlives.Manypeoplefearitcouldbethenextglobalepidemic,especiallyasscientistswhohavegoneintodetailstudyingtissuesamplesfromthebodiesofpeoplewhodiedofthe1918SpanishFluhaveprovedthatbirdfluisamodernadaptationofthatvirus.NamePeriodPlacesDeathtollBirdFlusince1997morethanahundredlivesScanPara4andCompletethetable.Q1:WhydidmanypeoplefearBirdFlu?.Oneoftheearliestepidemicsonrecordhappenedbetweenabout500and550CE.Scientistsnowestimatethatupto50%ofthearea’spopulationdiedfromtheepidemic,makingitoneofthemaincausesofthefalloftheRomanEmpire.ScanPara5andCompletethetable.NamePeriodPlacesDeathtollEpidemicsintheRomanEmpire500-550CERome50%ofthepopulationScanPara5andCompletethetable.NamePeriodPlacesDeathtollTheBlackDeath1330sAsiaandEuropeThen,inthe1330s,thisepidemicreturnedthistimeinAsia.ltspreadrapidlytoEuropeandbecameknownas“TheBlackDeath"becauseonevisiblesymptomwasblackspotsonthebody.·ScanPara6aboutthetheSpanishFlu.·Centurieslater,theGreatFluEpidemicof1918,alsocalledtheSpanishFlu,struckneartheendofWorldWarl.Familieswhohadonlyjustgotthroughthewarnowhadtoburytheirlovedoneswhohaddiedofthedisease.Asaresultofthewar,morepeopleweretravellingandmovingperhapsthaneverbeforeinhistoryandthiscausedtheepidemictospreadworldwide.Havingkilledupto50milionpeoplein18months,theSpanishFluisbelievedtohavebeenthemostsevereepidemicinhistory,Morepeoplediedofthefluthandiedinthewar.Initially,manypeoplebelievedthatsuchepidemicsnolongerposedathreatuntilveryrecentlywhenSARSbecameacauseforconcern.NamePeriodPlacesDeathtolltheSpanishFlu1918-theendofWorldWarI50millionScanPara6andCompletethetable.

Q2:WhydidtheSpanishFluspreadsowidely?·ScanPara7abouttheSARS.TheSARSepidemicbeganin2002withacaseoflungdiseaseinGuangdongProvince.ltspreadtoCanada,VietnamandSingaporeandlasteduntil2003.SARSwasexaminedbyscientists,whowereconfusedbythisnewdiseaseandwantedtolearnmoreaboutitanditscauses.Infectionrateswentupsteadily,andinthecourseoftheoutbreak,about8,000peoplewereinfectedoverninemonths.SincetheendoftheSARSepidemic,scientistshavebeendoingtrialsontreatmentstopreventanyfutureoutbreaks.NamePeriodPlacesDeathtollSARS2002-2003China,Canada,VietnamandSingapore·Then,from2013to2016,therewasthemostwidespreadoutbreakoftheEbolaVirusDisease(EVD)inWestAfrica,whichresultedinamajorlossoflifeinanumberofwestAfricancountries.11.310deathswereofficiallyrecorded,buttheactualnumberofdeathsisprobablymuchhigher.Theviruswasextremelyinfectiousandthesurvivalratewasaslowas30%insomeareas,indicatingthatveryfewpeoplegotoverit.ScanPara8about(EVD).·ScanPara8andCompletethetable.NamePeriodPlacesDeathtollEVD2013-2016WestAfricamorethan11310death·ScanPara9andfindthesolutions.Despite,orperhapsbecauseof,theepidemicstheworldhasfacedinrecentyears,governmentsworldwidehaveunderlinedthefactthattheywantthoroughandsystematicmedicalresearchonepidemicstogetatthecausesandcomeupwithcuresassoonaspossible.Countrieswillneedtoworktogethertodothisbecauseteamworkamongnationsacrosstheglobecansavelives.Talkaboutwhatyouhavelearnedab