I've noticed that occasionally after getting wounded and covered in blood or other effects that when they disappear they can sometimes leave some artifacts behind (at least when I've noticed this happening it's been after those situations.)
I haven't had "red hands," but at one point I did notice that my hands were crazy white with some odd brown markings on them.
In any case, quicksaving and reloading seemed to refresh it and the fix the issue - hopefully down the road Bethesda can prevent this in a patch. I'm by no means an expert but it just feels to me like a side effect of some of the special effects and the texture layers not always updating properly.
Unfortunately quick save and reloading does not help. Even shutting down and rebooting not.
It is really worse now. It totally ruins my view when I'm sneaking in first person. I only see red "polygons".
The only workaround is using a power armor. The view there is not covered by red polygons. Any idea how I can set the camera into the same position if O'm not using power armor?
Update: Finally got a solution in an other forum: "Player.removeitem 001e22e5" solves it.