【素材】Unit 1 文档1854 Broad Street cholera outbreak（人教）

《【素材】Unit 1 文档1854 Broad Street cholera outbreak（人教）》由会员上传分享，免费在线阅读，更多相关内容在应用文档-天天文库。

1、1854BroadStreetcholeraoutbreakBroadwickStreetshowingtheJohnSnowmemorialandpubThe1854BroadStreetcholeraoutbreakwasasevereoutbreakofcholerathatoccurrednearBroadStreet(nowrenamedBroadwickStreet)inSohodistrictofLondon,Englandin1854.ThisoutbreakisbestknownforJohnSnow'sdisc

2、overythatcholeraisspreadbycontaminatedwater.BackgroundInthemid-19thcentury,theSohodistrictofLondonhadaseriousproblemwithfilthduetothelargeinfluxofpeopleandalackofpropersanitaryservices.Manycellars(basements)hadcesspoolsofnightsoilunderneaththeirfloorboards.Sincetheces

3、spoolswereoverrunning,theLondongovernmentdecidedtodumpthewasteintotheRiverThames.Thiscausedmassivewatercontaminationandledtothecholeraoutbreak.OutbreakOn31August1854,afterseveralotheroutbreakshadalreadyoccurredelsewhereinthecity,amajoroutbreakofcholerastruckSoho.DrSno

4、wlatercalledit"themostterribleoutbreakofcholerawhicheveroccurredinthekingdom."Overthenextthreedays127peopleonornearBroadStreetdied.Inthenextweek,threequartersoftheresidentshadfledthearea.By10September,500peoplehaddiedandthemortalityratewas12.8percentinsomepartsoftheci

5、ty.Bytheendoftheoutbreak616peopledied.JohnSnowInvestigationOriginalmapbyDr.JohnSnowshowingtheclustersofcholeracasesintheLondonepidemicof1854Snowwasaskepticofthethen-dominantmiasmatheorythatstatedthatdiseasessuchascholeraortheBlackDeathwerecausedbypollutionoranoxiousfo

6、rmof"badair".Thegermtheorywasnotwidelyacceptedbythistime,soSnowwasunawareofthemechanismbywhichthediseasewastransmitted,butevidenceledhimtobelievethatitwasnotduetobreathingfoulair.HefirstpublicizedhistheoryinanessayOntheModeofCommunicationofCholerain1849.In1855aseconde

7、ditionwaspublished,withamuchmoreelaborateinvestigationoftheeffectofthewater-supplyintheSoho,Londonepidemicof1854.Bytalkingtolocalresidents(withthehelpofReverendHenryWhitehead),heidentifiedthesourceoftheoutbreakasthepublicwaterpumponBroadStreet(nowBroadwickStreet).[1]A

8、lthoughSnow'schemicalandmicroscopeexaminationofasampleoftheBroadStreetpumpwaterwasnotabletoconclusivelyproveitsdanger,hisstu