Refreshing my variable every second or so?

Hi I had a problem with my script. It was: it didn't refresh my variable so it thought when you first join and if there is one zombie then... Can you help?

if Zombies == 0 then
        print("Survivors won")
        wait(1)
        for i,v in pairs (game.Players:GetPlayers()) do
    v.Character:MoveTo(Vector3.new(-6, 0.5, -11))