A honeybee hive, with its large stores of pollen, wax, and honey, is like a fortress guarding treasure: with strong defenses, but a bonanza for enemies that can overcome those. More than 30 parasites of honeybees are known, spanning protists, viruses, bacteria, fungi, and arthropods—and this number keeps growing. As a result, beekeepers are always on the lookout for new ways to protect their precious hives.