A recurrence, breakout, or revival of something after a previous period of abatement or inactivity.
From the Latin, recrudescentia, 'to break out again', formed from re-, 'to happen again', and crudescere 'to become raw'.
Recently, there has been a recrudescence of people who form a large part of their diet from home-grown food.
Also, hopefully this posting has sparked a recrudescence of me posting words on my assigned day. =D