Check your resistances.
Bees and wasps use poison.
If you have too low poison resistance they'll kill you easily.
Maybe you have resistance bug (it activates when you equip item that gives you +1 Magic Barrier).
If you have it, download the latest patch
here and it'll fix your problem. <img src="/ubbthreads/images/graemlins/winkwink.gif" alt="" />