Among other diseases of a bacterial nature paralysis is most
noticeable, although not to be dreaded as foul brood. It affects the
adult bees only, producing a paralyzed condition of their members and
a swelling up of their bodies. The diseased bees, often set upon by
other workers, lose the hairy covering of their bodies, and, black
and shiny in appearance, may often be seen wriggling away from their
hives to die. In such cases the working force of the affected colony
frequently becomes so greatly reduced as to preclude any return in
the form of honey or swarms during the given season. The source from
which the bees obtain the original infection is unknown, but, once in
the apiary, it is spread mainly by the entrance of affected workers
into healthy colonies, and probably also by the visits which bees from
healthy colonies make to the diseased ones, the latter often being
so weakened in numbers as to be unable to protect their stores from
healthy bees out on robbing expeditions.
Ordinary paralysis may generally be cured by strewing powdered sulphur
over the combs, bees, and along the top bars of the frames, the
precaution first having been taken of removing all unsealed brood. This
brood would be killed by the application of sulphur, but as there is no
danger whatever of spreading the disease by the transfer of brood or
honey from one hive to another, provided absolutely every one of the
adult bees has first been shaken or brushed from the combs, the latter
may be given to healthy colonies which need strengthening.
Another simple plan for getting rid of the disease and yet utilizing
the available strength of the affected colonies is to close their hives
at night and move them a mile or more, locating them, if possible,
outside of the range of other bees. As the brood in these colonies
remains healthy all that is sealed or even well advanced in the larval
stage may have the bees shaken from it and be distributed among the
remaining colonies of the apiary. The bees of the diseased colonies
thus become rapidly reduced in numbers, and several of the colonies
themselves may soon be combined, the best queen being selected to
continue egg deposition. Eventually the diseased apiary becomes, by the
removal of the developing brood and the death of the old bees, reduced
to nothing. None of the queens should be saved nor should any of the
adult workers be returned to the healthy apiary.
A combination of the sulphur cure with the last plan mentioned--that
of getting rid of the disease through the removal of brood combs from
affected colonies--is really, all in all, the best procedure. When a
fairly strong colony has been made up by shaking the adult bees of
two or more together and this removed to an isolated locality, the
application of sulphur may be made before any brood has been started.
It is well, also, to replace the queen with a vigorous one from stock
entirely unrelated to the diseased bees. Should any signs of the
disease reappear, constant removal of the brood should be followed, as
mentioned in the preceding paragraph.
Other bacterial diseases, though existing, have developed only very
locally or have been too limited in the amount of injury inflicted to
require special mention here.