Hi,
you really should look up more information on this topic because I can only give you couple of the most important pointers.
This topic is the most important one that you may encounter when beekeeping.
YOU should really know all about it before rushing in and doing something that you may regret.
1. Determine why there are no bees in your hives first.
a. If they were all moved to new hives it is OK.
b. If they all died in your hives, the bees that you put in will suffer for a year and then will have most gruesome death .
(and I truly wish I was kidding here)
Question is why? because the hive is filled with spores of many illness such as american, European foul-brood, nosemosa and so on.
Beekeepers avoid going to people that have couple of old hives in the
yard. That is how bad it is.
On the other hand if the bees were moved and the wax moth came after you need to sterilize the hive. You do it by a strong blowtorch. Use it until the wood becomes black. After that use bleach to sterilize them for the second time. Filling a barrel and tossing hives in it would be the best solution.
(naturally it comes in some percentage I do not know from the top of my head -something like 5%) Washing them up also works but not as well.
You are much better off with 2 healthy colonies than with 10 sick ones that you will end up burning (it is the law to burn if some diseases are spotted).
If I would need to sum it up in a short sentence it would be:
OLD HIVES IN WHICH BEES DIED = PLAGUE