The bees in the above video aren't dead, but they're about as zombified as bees could be. They're suffering from just one of the many ailments putting honey bee colonies under pressure: a devastating parasite.
When the parasitic fly Apocephalus borealis crosses paths with certain species of bee — increasingly, the european honey bee — it aggressively pursues the bees and lays its eggs inside them. You probably don't need me to tell you that having another species grow and hatch inside you is no good. As the larvae grow, they feed off of the muscle and nervous system of their host bee, eventually destroying the brain. After a few weeks, they bust their way out of the bee's body by making a split between the head and the thorax.