My roommate in college had a Yamaha 750 street bike. He always wore a helmet due to the amount of wildlife (two-and four-legged) cavorting on the local back roads. He came home one Saturday afternoon with his helmet tied to the back of his seat. His helmet had a feature that allowed you to crack the faceplate slightly to allow air to flow through and out rear vents. A wasp had clipped the faceplate and got sucked into the helmet. By the time he recovered, pulled over and got his helmet off, the little bugger had stung his face, scalp and left ear about 6-8 times. He went riding the next day without the helmet (because it wouldn't fit over his swollen head). While traveling at about 55 MPH, he was struck right in the middle of the forehead by a monarch butterfly. It nearly knocked him off the bike! He had a welt the size of about 1/3 of a baseball and was a little pale and shocky from a near accident at that speed.
I asked him if he maybe he had stepped on a few too many ants lately.