Stan,
Regarding E.F.B., it is my understanding that "scales" that stick to the
wax are not produced.

The larvae die from being starvation.

If the larvae are removed then the infection is removed.

The continuation of the infection is due to not all infected individuals
dying- the infection is then passed on via the faecal material left in
the cell, which is cleaned by the house bees, allowing for contamination
of further individuals as they are fed.

If they die, it is before the cell is capped.

Regards
Peter