Wax moth and wax moth larvae
I often hear seasoned beekeepers say things like, "wax moth larvae are only a problem for weak colonies", or "wax moth larvae are only scavengers and something else must have weakened/damaged/killed the colony, first".
Yet, quite regularly, I have had very strong, thriving colonies receive varying degree of damage from wax moth larvae.
I regularly see a few wax moth larvae burrowing into sealed brood on solid frames of sealed brood, in extremely strong colonies. I regularly see patches of mature brood, who have removed their cappings, but cannot exit their cells because wax moth larval webs have locked them to the comb. In effect, buried alive, trapped in their wombs.
Certain Bt products, like Certan (B401) have greatly reduced these problems, but I've observed this issue as long as I've been keeping bees, and in every part of this country, where I've had bees. From San Diego, CA; Oak Harbor, WA; Key, OH; to Fort Walton Beach, FL, and many places in-between.
I am amazed that so many seasoned beekeepers have observed or interpreted differently. Perhaps it's my style of beekeeping -- I open and inspect many of my hives, almost daily; I frequently shake the bees from combs to observe the combs more closely. When I do this with combs of sealed brood, I frequently see wax moth larvae doing their dirty business. I also regularly see Varroa mites crawling on the surface of capped brood.