Some mold grew on some Turkish condiment leaf I ordered years ago, but since I've been running lucky. Spores are everywhere, as most of us learn cleaning the refrigerator.
I don't think so. I opened it maybe six months ago, and while I've been careful to keep the bag closed tight, I may have introduced spores when filling jars from the bag. Then again, I've not polluted any other bag or bulk tobacco....
I've resealed the bag, and will see if more develops over time.