Randy Oliver in his Scientific Beekeeping website has written many articles. In December '19 and January and February '20 he as wirtten about dysentry. If anyone is at a "Lockdown loose-end", they are well worth reading.
http://scientificbeekeeping.com/articles-by-publication-date/
The third article goes onto discuss insulation and top entrances - always a cause for a pub argument!
http://scientificbeekeeping.com/articles-by-publication-date/
The third article goes onto discuss insulation and top entrances - always a cause for a pub argument!
May your bees read the same books as you do.