Honey Bees are subject to various diseases and parasites. American and European foulbrood are two widespread communicable bacterial diseases that attack bee larvae. A protozoan parasite, Nosema, and a virus cause dysentery and paralysis in adult bees.
Two species of blood-sucking parasitic mites are in particular troublesome for beekeepers and are currently affecting wild Honey Bees worldwide. The Honey Bee tracheal mite lives in the breathing tubes of adult bees; the varroa mite lives on the outside of larvae and adults.
These mites have killed tens of thousands of Honey Bee colonies in North America during the past ten years. Scientific breeding programs are attempting to develop tolerant strains of domestic Honey Bees to replace the mite-susceptible ones currently used.
Tracheal mite infestations could be lowered by fumigation of the hive with menthol fumes. Varroa mites are controlled with a miticide or, in some European countries, with fumes of formic acid. Certain hive management techniques also could reduce infestations.
A lot of other animals prey upon individual Honey Bees, which can occasionally weaken colonies. Examples are cane toads and bee eaters (birds), which select off foragers near the honey bee colony entrance; robber flies, which take individual foragers as they visit flowers; and hornets and bee wolves (wasps), which can enter the nest or hive and steal larvae. Bears have an insatiable appetite for honey and bee larvae and may destroy many nests or hives in a single raid.
Honey Bee colonies used in commercial pollination and those kept in urban areas are exposed to pesticides, fungicides, fertilizers, and other agricultural chemicals and are frequently poisoned by accident. This is a major concern of modern beekeepers.