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It’safrightening disease.

Each year,between300and 500millionpeoplebecomeinfectedwiththedisease.Overonemillionofthemdie.

Most ofthem children…under theage offive…livinginAfrica.

It’smalaria…adiseasethathas beenaroundatleast since man

has…and probablyalotlonger.

Ifyouhave it,atfirstyoumightthinkthatyouhave theflu.

Thesymptomsareprettymuch thesame:fever,chills,headache,tiredness,sweating,nauseaand vomiting.

Andthesymptomsmaygoawayafterafewdays …onlytoreturnagain and again.

Astheparasitescausingtheinfection growand invademoreandmoreofthebody,thesymptomsworsen.

And,iftheparasitesthatinfectthevictimarePlasmodiumfalci-parum,things getprettyseriousprettyfast.Thisformoftheparasiteisresponsibleforabouthalfthecasesofmalaria intheworld.

Victimsofthiskindofparasitecan sufferawholearrayofsymp-toms: bleedingproblems,shock,liverorkidneyfailure,and coma.
Iftheydon’tgettreatmentquickly,theycan die.

Evenwithtreatment,about20percentwillstilldie.Andtreatmentsarelimited.

Inthepast,there weresomeveryreliableoptions.Asearlyasthe

1600s,nativesofPeru usedthebarkoftheChinchonatreetocurethisfever.Thebarkworked becauseitcontainedquinine, asub-stancethatdisruptedtheparasite’sreproductivecycle.

Jesuitmissionariesbroughtwordofthisremarkablecuretomanyother countrieswhere malaria wasepidemic,including Italyandother countriesinEurope.Demandforquinine soared.

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QuininefiguredintoAmerica’shistoryinmanyways.

Somesay,that, withoutthequinine, itneverwouldhave been possibletobuildthePanamaCanal.Malariawas aleading causeofdeathamongworkersbuildingthecanal.Withoutthehelpofquinine andother insectcontrolmeasures,thehuman costofbuildingthecanal wouldhave beentoohigh.

Twoimportant breakthroughsinthefightagainstmalaria happenedinthe1940s.

Thefirstwas thediscovery thatDDT(dichloro-diphenyl-trichlo-roethane)could beanextremelyeffective pesticidewhen usedagainstmosquitoes.

Thesecondwas thedevelopmentofasyntheticformofquinine, called chloroquine.Itwas veryeffective,had fewsideeffects, and, most importantly,was veryinexpensive.

Withthesetwotools, itlooked asifmalaria mightbeheadedforextinction.

But…notforlong.Toomanypeoplewereusing DDTfortoomanyother purposes.Asaresult, itwasaccumulating intheenvironmentand causingillnessand deathforanimalssuchasfalcons and salmon.Andpeoplefeared thatDDTwouldeventu-allycauseillnessand deathforhumans.

In1972, itbecameillegaltouseDDTintheUS.Othercountriessoonfollowedinprohibiting theuse ofDDT.

Theotherlegofthesolution was soonknockedoutaswell.Theplasmodiathatcausemalaria have ashort lifecycle. Thatmeansthatitdoesn’ttake themlongtodeveloparesistancetothreatsfromdiseasefighters suchaschloroquine.Beforelong,chloroquinewas nolonger effective intreatingmalaria, especially themost deadly kind.Theparasiteshad mutatedand chloroquinenolongerkilledthem.

Malariacamechargingback,even incountrieslikeSriLankaand Taiwan,where ithad previously beeninsharpdecline.And

itremainsathreat today toalmosthalftheworld’spopulation.

Part oftheupturninthislethaldiseasewas due topoverty.Develop-ingcountries–especiallyinsub-SaharanAfrica–didnothave theresourcestoprovide theirpeoplewithneededmedicalcare andpreventivemeasuressuchasbednetting.

But,there aremanyother environmentalfactorsthatareincreasingthethreat ofmalaria and other diseasescarried byanimals andinsects.

Animalsand insectsliveinhabitatsthataresuitedforthem.Theypreferaspecificrangeoftemperatures,aspecificrangeofprecipi- tation, and aspecificgeography.

Mynotes:

Itdoesn’tmatterwheretheseconditionsoccur. Insectsand other

animalswillleaveaplacethatnolongergivesthemtherighttem-

peraturerangeortherightgeographicfeature suchasaforest.

Andtheywillexpandtheirrangestoinclude areasthatnowfeature their“must-haves.”

Whentheymovetothese“other”areasvector animals and insects

(thosethatcarrydiseases)bringtheirdiseaseswiththem.

Awholepopulation—theexistingresidentsofthat“other”area—

getsexposedtotheseillnesses.

Andthispopulation hasn’t had achancetobuildimmunitytothenewdiseasestheyhave toface.

Tothem, theirnewneighborsareadeadly group.

That’swhat’shappeningnowwithmalaria. It’sbeengettinghotter in certain areasoftheworld,ifonlybyasmallfraction ofadegree.

Butthatsmallfraction isenoughforthemosquitoestoexpandtheirhabitats.

Thelethaldiseaseofmalaria isonthemove.

Asareothervector-borneillnesses…diseasessuchasLymeDis-

ease,yellowfever,WestNilevirus,and even denguefever.

Ourclimate ischanging…and soistheriskthatmoreand morepeoplewillgetnewand deadly diseasescarried byinsectsandanimals movingintonewhomes.

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