Sound like he developed adult onset reactions to a sting. I have been a state certified EMT in Virginia for many years and worked as a volunter on our local rescue squad for a while some time ago. It's not uncommon to see this and it could be a reaction to only one kind a bee but not likley. He needs to keep his eppi pin with him at ALL times from now on even in the winter! Odds are it will make him very lathargic and he still should seek medical attention for the first few times he uses it just to be on the safe side.