Vermont beekeepers say they face mite infestations, extreme temperature swings and the possibility of colony collapse. But a San Francisco State University professor says a new threat has arrived in Vermont: zombie bees.

Beekeeper Anthony Cantrell says he discovered the bees infected by a parasitic fly in his hive in October. Professor John Hafernik says they're the first of the zombie bees identified on the East Coast.

Hafernik says that a fly attaches itself to the bee and injects its eggs, which grow inside the bee. Hafernik says this is presumed to cause neurological damage resulting in erratic, jerky movement and night activity, "like a zombie."

Vermont Agricultural Production Specialist Stephen Parise says they are not sure if Cantrell's bees are an isolated occurrence.