The incidence of virus diseases in the honey bee

SUMMARY Chronic bee‐paralysis virus and sacbrood virus occur commonly in apparently normal honey‐bee colonies in Britain. Most sick adult bees not affected by Nosema apis, Malpighamoeba mellificae or Acarapis woodi have chronic paralysis and most dead larvae not affected by micro‐organisms have sacbrood. Both virus diseases are probably limited by hereditary factors, but unknown environmental factors also seem to influence disease. Paralysed bees from Australia, Canada, Eire, Germany and Mexico were found to be infected with chronic paralysis virus.