prEDiCting thE FuturE is risky BusinEss For A sCiEntist. it is sAFE to sAy, howEvEr, thAt thE gloBAlAiDs EpiDEmiC will gEt muCh worsE BEForE it gEts Any BEttEr. sADly, this moDErn plAguE will BE with us For sEvErAl gEnErAtions, DEspitE mAjor sCiEntiFiC ADvAnCEs.
As oF jAnuAry 2000, thEAiDs EpiDEmiC hAD ClAimED 15 million livEs AnD lEFt 40 million pEoplE living with A virAl inFECtion thAt slowly But rElEntlEssly EroDEs thE immunE systEm.ACCounting For morE thAn 3 million DEAths in thE pAst yEAr AlonE, thEAiDs virus hAs BEComE thE DEADliEst miCroBE in thE worlD、inAFriCA nEArly A DozEn CountriEs hAvE A rAtE highEr thAn 10%, inCluDing Four southErnAFriCAn nAtions in whiCh A quArtEr oF thE pEoplE ArE inFECtED、this is likE ConDEmning 16 000 pEoplE EACh DAy to A slow AnD misErABlE DEAth.
FortunAtEly, thEAiDs story hAs not BEEn All gloom AnD Doom. lEss thAn two yEArs AFtErAiDs wAs rECognizED, thE guilty AgEnt—humAn immunoDEFiCiEnCy virus, or hiv—wAs iDEntiFiED、wE now know morE ABout hiv thAn ABout Any othEr virus, AnD 14AiDs Drugs hAvE BEEn DEvElopED AnD liCEnsED in thE u.s. AnD wEstErnEuropE.
thE EpiDEmiC ContinuEs to rAgE, howEvEr, in southAmEriCA,EAstErnEuropE AnD suB-sAhArAnAFriC
A、By thE yEAr 2025,AiDs will BE By FAr thE mAjor killEr oF youngAFriCAns, DECrEAsing liFE ExpECtAnCy to As low As 40 yEArs in somE CountriEs AnD singlE-hAnDEDly ErAsing thE puBliC hEAlth gAins oF thE pAst 50 yEArs.
it isAsiA, with its hugE populAtion At risk, thAt will hAvE thE BiggEst impACt on thE gloBAl sprEAD oFAiDs. thE mAgnituDE oF thE inCiDEnCE CoulD rAngE From 100 million to 1 Billion, DEpEnDing lArgEly on whAt hAppEns in inDiA AnDChin
A、Four million pEoplE hAvE AlrEADy BEComE hiv-positivE in inDiA, AnD inFECtion is likEly to rEACh sEvErAl pErCEnt in A populAtion oF 1 Billion. hAlF A millionChinEsE ArE now inFECtED; thE pAth oFChinA’s EpiDEmiC, howEvEr, is lEss CErtAin.
An ExplosivEAiDs EpiDEmiC in thE u.s. is unlikEly. instEAD, hiv inFECtion will ContinuE to plAguE in ABout 0.5% oF thE populAtion.But thE ComplExion oF thE EpiDEmiC will ChAngE. nEw hiv inFECtions will oCCur prEDominAntly in thE unDErClAss, with rAtEs 10 timEs As high in minority groups. nEvErthElEss,AmEriCAn pAtiEnts will livE quAlity livEs For DECADEs, thAnks to ADvAnCEs in mEDiCAl rEsEArCh.DozEns oF powErFul AnD wEll-tolErAtEDAiDs Drugs will BE DEvElopED, As will novEl mEAns to rEstorE thE immunE systEm.
A、CurE ForAiDs By thE yEAr 2025 is not inConCEivABlE.But ConstrAinED By EConomiC rEAlity, thEsE thErApEutiC ADvAnCEs will hAvE only limitED BEnEFit outsiDE thE u.s. AnD wEstErnEuropE.
ACCorDing to thE pAssAgE, whiCh oF thE Following stAtEmEnts is truE
A、in inDiA, thE inFECtion rAtE Almost rEAChEs 12 pErCEnt oF its populAtion.
B、inChinA, ABout 50 000 pEoplE ArE inFECtED with hiv.
C、AiDs EpiDEmiC hAD CAusED 15 000 000 DEAths in thE wholE worlD By jAnuAry 2000.
D、in thE unitED stAtEs, hiv inFECtion will go on to AttACk ABout 5% oF thE wholE populAtion.