Re: Help! Sudden onset dysentery
Long as you have not fed them anything you shouldn't have, it's most likely nosema apis, but not nosema cerana.
If the weather is OK plus they are flying and foraging freely, the hive will likely recover. However if there is as much poop as you say, it would be a good plan to clean it up some. Does your hive have a screened bottom board? If it does you could (carefully) use say, a garden hose and small brush, finish off by spraying some diluted bleach on the affected areas, and do it on a good day when it will dry out fast.
44 years, been commercial, outfits up to 4000 hives, now 120 hives and 200 nucs as a hobby, selling bees. T (mostly).