专题检测卷(二十)阅读理解第一节(建议用时:25分钟)A体裁议论文题材禽流感的防治词数373Tiredness,coughing,arunnynoseandasorethroat—amongallsicknessesthereisprobablynonemorecommonthantheflu,whichweallgetnowandthen
However,birdfluisacompletelydifferentstory
Tenyearsago,theH5N1birdflusweptacross15countries,includingChina,withsufferersreportingchestpain,difficultybreathing,feverandseverecoughing
Morethan600peoplewereinfected,andabout60percentdied
NowanothertypeofbirdfluhitShanghaiandthreeneighboringprovinces,andthistimethevirusiscalledH7N9
BytheafternoonofApril11,thenewvirushadtakenninelivesoutof35infected,accordingtoXinhuaNewsAgency
The“H”and“N”inthevirus’namereferstotwokindsofproteinsonthesurfaceofthevirus
Anychangeofthenumbersofthetwoproteinsindicatesanewmutation(变异)
Mostofthemutationsonlyaffectbirds,suchaschickensandpigeons,anddo