Commander Sisko:  We need to find out who created this virus .
Commander Sisko: You 're our best hope .
Major Kira: Eighteen years is a long time .
Odo: Besides , even if she finds who did this , that 's no guarantee they can help us .
Commander Sisko: We just have to hope they remember the antidote .
Odo: That 's assuming they ever bothered to create _ one _ .