Reading your post, Lee, jogged my memory and brought forth recollections of another biological control organism that helps destroy wax moth larvae. On many occasions I have seen tiny parasitic wasps searching among wax moth larvae in my infested hives. I never identified the species in my hives, but, in the literature, I have come across the name (although it may be a different species than the one I have seen in Israel): Apanteles galleriae Wilkinson (Hymenoptera: Braconidae) as a wax moth parasitoid. The females lay their eggs inside the wax moth larvae. The tiny wasps complete their development inside the larvae, feeding on their insides as they grow and, in the process, kill the wax moths.
In my opinion, the BT is much more effective, but biological control becomes more and more efficient as the number and variety of natural control agents increases.