Than sorry, get yourself some enzyme cleaner (you can get bottle of it at Prairie West) and spray the droppings and area down first. Then you can vacuum or sweep.
I know you really should not mix bleach with "droppings" of most species as the ammonia can mix but with mice droppings there is so little wet matter I feel safe doing it - I skip the enzyme and spray the area with bleach and let dry. After I have cleaned up the area I bleach clean again and usually go over with the enzyme cleaner after all is said and done. I am a bit of a germaphobe that way.
You really should never sweep or vacuum rodent droppings as there is too much chance of making diseases airborne.
I found this link for more help...
http://www.orkin.com/rodents/mouse-control/how-to-clean-up-after-mice-infestation/