Hives of western honey bees infected with Nosema ceranae are wiped out within eight days indicating that CCD may be caused by N. ceranae. A research team claim to have ruled out many other potential causes,Asian Parasite Killing Western Bees – Scientist, Planet Ark, SPAIN: 19 July 2007 however, a 2009 survey of US CCD-affected bee populations found only about half of the colonies sampled, both in CCD and control populations, were infected with N. ceranae.
