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1、EpidemicsthroughouthistoryWithrecentnewsreportsconnectedBirdFluwithakillerepidemicinthepast,JimSmithlooksthroughthehistoryofepidemicsforcluesaboutwhatthefuturemighthold.BacteriaandviruseshavebeenaroundsincethebeginningoflifeonEarthandmanyoftoday’sdiseaseshaveexistedaslongashuman
2、shave.Itisimportanttolookatthespreadofdiseasesthroughouthistorytodiscoverthecausesandeffectsofepidemics,andhopefully,foreseeandpreventtheminthefuture,especiallyasscientistsprovedthatBirdFluisamodernadaptationofthesamevirusoftheSpanishFlu.Oneoftheearliestepidemicsonrecordhappened
3、about500-550ADwhentheRomanemperoratthetimewasattemptingtorebuildtheRomanEmpire.Thisepidemic，whichwascalledJustinian’sPlague,sweptthroughNorthAfrica,theMiddleEastandEurope.Scientistsnowguessthatupto50%ofthearea’spopulationdiedfromthisepidemicmakingitoneofthemaincausesofthefalloft
4、heRomanEmpire.Inthe1330’s,theepidemicreturned,thistimeinAsia.Thisspreadrapidlyandbecameknownas“TheBlackDeath”asonesymptomwasblackspotsonthebody.InurbanareasalloverEurope,Asia,AfricaandtheMiddleEast,uptoonehalfofthepopulationwaslosttotheBlackDeath.Anotherepidemicthatspreadinsimil
5、arconditionswastheSpanishFlu.Itstruckabout1918-1920andleftfamiliesmourningworldwide.Havingkilledupto50millionpeoplein18months,withatendencytostriketheyoungandfitratherthantheold.Morepeoplediedofthefluthandiedinthewar.Yet,somehow,itwasforgottenbyhistoryuntilveryrecentlywhenSARSbe
6、cameacauseforconcern.TheSARSepidemicbeganin2002withalungdiseaseinGuangdongProvinceandspreadquicklyafterDrLiuJianjun,thecarrier,cametoHongKongandpassedthevirustopeoplewhocarriedittoCanada,VietnamandSingapore.Overninemonths,8000caseswerereportedinover30countriesacrossfivedifferent
7、continentsand774peopledied.AlthoughthesestatisticsaremuchlessimpressivethanthosefortheSpanishFlu,SARSwasstillveryalarmingforafewkeyreasons.Generally,SARSsymptomsincludeahighfever,bodyaches,andheadaches. However,astheillnessprogresses,mostpatientseventuallydeveloppneumonia. TheSA
8、RSvirusspreadsmainlybyclosehumancontact,eithert
