UnseenEnemyisanessentialexplorationofreasons21st-centurypopulationsareexperiencingar UnseenEnemyisanessentialexplorationofreasons21st-centurypopulationsareexperiencingarashofdiseasesthatwereonceonlyoutbreaks,buthavenowbecomefull-blownepidemics.Thisincreasedriskthatweface,andthewayssocietyandindividualscanworktogethertoreducethatrisk,areexplainedtothepublicthroughthecasestudiesofthreeepidemics:Ebola,infl.