There has been many communications regarding wax moth infestation and
certainly freezing will work but the frames/boxes do need to be left for at
least a week to kill the larvae.
The other method would be to use a product containing bacillus thuringiensis
a natural method for killing the larvae. The product that is available in
England is called Certan and manufactured by Swarm S.A., it is a liquid
which you dilute with water in a hand sprayer and spray both sides of all
frames with this liquid. When the wax moth worms ingest the wax coated with
the spray the bacillus gets to work in their gut and kills them off. The
bacteria is specific to lepidopterans (moths and butterflies caterpillars)
and does not harm the bees when they use the frames at a later stage. It
needs to be re-applied each year in view of its natural properties as there
are no chemical residues.
It certainly works over here and stops further damage to the frames.
Hope this is of some help.
Peter Dalby, Chairman BBKA