I try to run a very clean operation by not buying and implimenting old used equipment.
And as my operation ages, I know the potential to have AFB grows.
But to diminish the possibility I try to replace combs as they age on a 5-6 year cycle, and clean frames as Finski as stated (nice work Finski).
I have done my homework on the disease. I have read the old timers papers and even the aussy paper that describes the "Shake Method" to "clean-up" AFB. But its pretty tough to eliminate all the spores when the bees themselves are active carriers of the spores in their honey guts. I've also have been in numerous camps that toted the use of medications in various on-label and off-label methods. The immediate results are the same, the symptoms subside, but ultimately, the disease returns.
The bottom line is there are numerous ways to diminish the number of spores in the colony to supress the disease enough to make it appear that the disease is gone. But often it is just in hiding, and microscopic spores can easily hide in places we don't see or consider. The safest bet is to burn everything wood, and boil everything else as Finski described.
Why worry about saving a little bit of equipment, if you're going to have replace more costly bees each season? (plus, you become an unfriendly disease reservoir to infect other colonies around you.)