=Retarded?== 
 [edit] Sacbrood virus (SBV) 
 Morator aetatulas is the virus that causes sacbrood disease. Affected larvae change from pearly white to gray and finally black. Death occurs when the larvae are upright, just before pupation. Consequently, affected larvae are usually found in capped cells. Head development of diseased larvae is typically retarded.  
 :Surely there is a better and less confusing way to say this.