The Gnats are Swarming...

How is it that such a useless insect, impervious to any and all bug sprays, can have such an uncanny ability to find any open orifice on the human body and infiltrate said orifice?? I have gnats in my ears, nose, mouth and, most annoying, stuck between my eyes and my glasses. What's worse, our particular gnats are biters. They don't just leave a small, slightly itchy bug bite, they leave a welt the size of a dime. I hate them.