let it dry out well. Pull out the contaminated insulation and have new ready for re install. I would turn of that breaker to that light receptacle or tape it off. Open the area up and many times with airing, things are not as bad as they look now.
If you can, get some bleach in a spray bottle and AFTER all has thouroughly dried out, spray this around the area on the inside, this will kill any bacteria or spores.