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1、Team#40764Page1of25StochasticandDeterministicModelsoftheEradicationofEbolainWestAfricaSummaryHereinwepresentstochasticanddeterministicmodelsforthecurrentEbolaoutbreakinWestAfrica.Thegeneralapproachusedforbothmodelsistodividethepopulationintothreestates,infectedpeop
2、le,healthyvulnerablepeople,andhealthyimmunepeople.Wethenassignparametersrepresentingtheratesatwhichpossibletransitionsbetweenthesestatesoccur.ThisenablesustopredictthespreadoftheEbolavirusforanyinitialconditions.Toverifythegeneralapproach,stochasticanddeterministic
3、predictionsarecomparedwithWorldHealthOrgnisation(WHO)dataforthemostrecenteighty- vedaysoftheoutbreak.Toensurethegeneralmethodisrobust,weinvestigatefourregions:Guinea,Liberia,SierraLeone,andWestAfricaasawhole.Weestimatethestatetransitionrateparametersusingavailables
4、tatistics,andshowthatrealisticparameterestimatesresultinpredictionsthathavegoodagreementwithknowndata.Wethenusebothmodelstopredictthefutureoftheoutbreak,assumingpresentconditionsremain.Thisprovidesabasiswithwhichtocomparethee ectsofdi erenttreatmentmethods.Inoursen
5、sitivityanalysis,weindependentlyconsiderthee ectofthreetreatmentmethodsonthenumberofdeathscausedbyEbola.Thethreetreatmentmethodstestedare:improvementsinmedicalservices,improvementsinthequalityandquantityofmedicine,anddistributingavaccine.Stochasticsimulationsforsev
6、eraltreatmentregimesareperformedovertheshort-term(sixmonths),andmedium-term(twoyears).Thisenablesustodeterminetherelativee ectivenessofdi erenttreatmentmethods,andwhichnationsshouldbetargetedintheapplication.Wethengeneralisetheinvestigationusingthedeterministicmode
7、l.Byanalysingthestabilityof xedpointsinthemodel,wedeterminetherelationshipbetweenparametersrequiredtoeradicateinfectionsinthelong-term.Qualitatively,key ndingsofthesensitivityanalysisare:Themoste ectiveshort-termstrategyinallcountriesisproducingalargequantityofimp
8、rovedmedicineThemostecientstrategyforreducingmedium-termdeathsistoimprovemedicalservicestoisolateinfectedpatientsShort-termstrategieswillbemos
