A swarm that has been captured is likely to have some varroa on the bees so when it is put into a hive so it's a good idea to vape them a few days after they have been hived when there is no sealed brood - you will kill most of the resident varroa at that stage. If it has come from your own bees then it will depend upon the varroa levels in the parent colony.
A commercially purchased Nuc should really come with the knowledge that the bees have been treated at some point for varroa and they should, therefore, not require treatment. If you suspect there are varroa present in a nuc you should do a sugar roll to confirm and then treat as required .. if there is sealed brood (which there should be in a purchased nuc) and they need treatment then you should be doing three vapes at five day intervals to be certain.
If it's a Nuc that you are creating from your own bees then I know you have treated them so there should be no need for further treatment until the Autumn unless they are showing signs of infestation.