They are preparing for an 'outbreak of' the virus.
an 'outbreak of' violence/war
a cholera 'outbreak'
(..) Good. Don't tell anyone about the zombies. Never ever. No, wait... ...can I at least tell Jake? Tell me about what, dude? You know, about the outbreak of zom-- Alright, what's going on? Uhh, nothing at all, buddy! Hey, dude. I think you and Bubblegum are up to something. Ahha ah, what? No, no way. (..)2010 TvShow: Adventure Time Title: Slumber Party Panic Season: 1 Episode 1