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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.Thisprovidesabasiswithwhichtocomparetheeectsofdierenttreatmentmethods.Inoursen
5、sitivityanalysis,weindependentlyconsidertheeectofthreetreatmentmethodsonthenumberofdeathscausedbyEbola.Thethreetreatmentmethodstestedare:improvementsinmedicalservices,improvementsinthequalityandquantityofmedicine,anddistributingavaccine.Stochasticsimulationsforsev
6、eraltreatmentregimesareperformedovertheshort-term(sixmonths),andmedium-term(twoyears).Thisenablesustodeterminetherelativeeectivenessofdierenttreatmentmethods,andwhichnationsshouldbetargetedintheapplication.Wethengeneralisetheinvestigationusingthedeterministicmode
7、l.Byanalysingthestabilityofxedpointsinthemodel,wedeterminetherelationshipbetweenparametersrequiredtoeradicateinfectionsinthelong-term.Qualitatively,keyndingsofthesensitivityanalysisare:Themosteectiveshort-termstrategyinallcountriesisproducingalargequantityofimp
8、rovedmedicineThemostecientstrategyforreducingmedium-termdeathsistoimprovemedicalservicestoisolateinfectedpatientsShort-termstrategieswillbemos