Well, this happened to me once when I hit a bee hive with my head, and another time when my group took a rest, and the fire ants decided to join us. Flying into the sting of an insect is unlikely because for most of them, their stinger retracts, and they only push it out when they want to sting. Ive had an assortment of bugs hit me while Im riding, and if there is heavy wind, theres nothing they can do. Insects usually dont want to attack unless they feel threatened (just like most other animals) so just steering clear and keep moving would work the best. Having one fly into a jersey or helmet sucksucks a lot, so just take it off, dont try to shake it out.