The Big Three: Nosema, Varroa, and Foulbrood

These three pests and diseases are the triple-threat of the beekeeping world. Not that there aren't a lot of other things that can harm or kill bees (pesticides, chalkbrood, wasps, bears... just to name a few), but if you consider all the potential threats, it's pretty overwhelming! So just start by learning about the signs and protocols for monitoring for these:

Parasite and Disease Resources | Pollinator Network @ Cornell

Pests, Disease, Varroa mites, nosema, pathogens, virus