I had an wasp experience last summer. We were sitting in the pub garden one lunchtime, and there were lots of wasps buzzing around and generally being irritating.

So, we got to talking about the fact that none of us had ever been stung by a wasp (I've been stung by a bee before, though -- and bitten by a horsefly) when I felt an itch on the back of my leg. I went to scratch it -- big mistake. A wasp had crawled up the back of the leg of my jeans, and wasn't best pleased about being scratched like an itch.

I said "it's at this point that we find out if I'm allergic to wasp stings". Fortunately, the pharmacy was fairly close, so I walked over there and grabbed some Wasp-eze.

And, yes, it was still slightly swollen and very itchy 5 or 6 days later.