That's an interesting question and maybe someone on the board actually knows for a fact.
I just always assumed that they use standard protocol in the government approved arsenal. A regiment of POISONS and ANTIBIOTICS just in case they might by the odd chance happen to come across something bad. Sorry for yelling.
In the end I suppose it doesn't matter what they do with the bees. They wind up in your hands where they are only treated with tender loving care or tuff love if that need to be the case.
"Success is not final, failure is not fatal: it is the courage to continue that counts." Winston Churchill