Cineen

The Cineen were a race of would-be conquerors who attempted to develop a nano virus, but lacked the facilities to properly control it. The virus eventually escaped and, instead of becoming the dominant race of their home system, they ended up practically back in the Stone Age. Their planet went under quarantine for a hundred years, the projected amount of time for the virus to run its course.

The Cineen were used as an example, that growing a nano virus was not something to be taken lightly.