Honey bees in the US are under stress from a variety of factors including parasites. The Varroa mite, Varroa destructor, was first detected in the US in 1987. Varroa mites, if not managed by bee keepers, can kill entire honey bee colonies. Varroa mites are ectoparasites. They live on the outside of the honey bees, pierce their cuticle and feed on the honey bee hemolymph (blood). The mites are especially destructive to honey bee larvae.In addition to the direct damage to honey bees by feeding, Varroa mites can transmit deformed wing virus, a pathogen that can be fatal to developing larvae. Honey bees are not entirely defenseless against diseases. Colonies can detect infected individuals and remove them from the colony. A recent study by German Scientists found that bee larvae infected with deformed wing virus will produce an odor as the disease progresses. This odor is detected by the adult bees. Removal of infected larvae slows the spread of the disease and helps protect the colony.