When we had a house in Spain we used to get lots of wasp nests around the eaves. As it was only a single storey home, they were very close to doors and windows, so we would wait until dusk when they had all gone into the nest, and then heavily spray with a normal wasp/fly spray, and then jump back as wasps rained down on the concrete. Never got stung once, but where we live now, I inadvertently disturbed a wasp nest where there was no sign of activity, and was stung more than 30 times, it's the worst experience I've ever had, I had wasps in my hair in my clothes in my glasses, everywhere! I ran indoors and stood under the downstairs shower, and watched as they fell out of my hair etc. It took me 3 days before I was anywhere near back to normal, and naturally after that, I am VERY wary and extremely glad that I don't appear to be allergic to them as our nearest hospital is 20 minutes away!