Symptoms. No symptoms in most people. Most people (8 out of 10) infected with West Nile virus do not develop any symptoms. Febrile illness (fever) in some ...SkipdirectlytositecontentSkipdirectlytopageoptionsSkipdirectlytoA-ZlinkSkipdirectlytoA-ZlinkSkipdirectlytoA-ZlinkWestNilevirusSectionNavigationCDCHomeFacebookTwitterLinkedInSyndicateSymptoms,Diagnosis,&TreatmentEspañol(Spanish)MinusRelatedPagesSymptomsNosymptomsinmostpeople.Mostpeople (8outof10)infectedwithWestNilevirusdonotdevelopanysymptoms.Febrileillness(fever)insomepeople.About1in5peoplewhoareinfecteddevelopafeverwithothersymptomssuchasheadache,bodyaches,jointpains,vomiting,diarrhea,orrash.MostpeoplewiththistypeofWestNilevirusdiseaserecovercompletely,butfatigueandweaknesscanlastforweeksormonths.Serioussymptomsinafewpeople. About1in150peoplewhoareinfecteddevelopasevereillnessaffectingthecentralnervoussystemsuchasencephalitis(inflammationofthebrain)ormeningitis(inflammationofthemembranesthatsurroundthebrainandspinalcord).Symptomsofsevereillnessincludehighfever,headache,neckstiffness,stupor,disorientation,coma,tremors,convulsions,muscleweakness,visionloss,numbnessandparalysis.Severeillnesscanoccurinpeopleofanyage;however,peopleover60yearsofageareatgreaterrisk.Peoplewithcertainmedicalconditions,suchascancer,diabetes,hypertension,kidneydisease,andpeoplewhohavereceivedorgantransplants,arealsoatgreaterrisk.Recoveryfromsevereillnessmighttakeseveralweeksormonths.Someeffectstothecentralnervoussystemmightbepermanent.About1outof10 peoplewhodevelopsevereillnessaffectingthecentralnervoussystemdie.DiagnosisSeeyourhealthcareproviderifyoudevelopthesymptomsdescribedabove.YourhealthcareprovidercanorderteststolookforWestNilevirusinfection.Tolearnmoreabouttesting,visitourHealthcareProviderspage.TreatmentNovaccineorspecificantiviraltreatmentsforWestNilevirusinfectionareavailable.Over-the-counterpainrelieverscanbeusedtoreducefeverandrelievesomesymptomsInseverecases,patientsoftenneedtobehospitalizedtoreceivesupportivetreatment,suc