@Krimzon - Here is what is known about the Scourge:
-It attacks both biological and technological items
-It's a ruthless SOB
-It doesn't seem to survive Planetfall, but it never was really given the chance to do so (and what Planets that had once been infected, were sterilized from orbit)
-Detection methods are crude at best, until the Scourge shows itself (and there's not much way, at this point, to determine the extent of the infection)
Your Home System is secure from the Scourge, for now, but if it ever ends up in any System you have colonized, it will be a double-whammy for you. The best advice you can get right now (at current tech levels) is to avoid Scourge-infected systems at all cost.