If you’re a remotely serious cyclists and you wear a helmet (which any remotely serious cyclist should), you’ve undoubtedly come-across the situation where a bug direct-injects himself into your helmet and won’t come out. Helmets in the late 80’s and 90’s had lycra covers on them that covered the air holes and prevented this problem. However, it seems like many of the most popular helmet companies seem to not think that getting a hornet, wasp, or a mad bee in your helmet isn’t a problem.
I did some research on this last night and found that quite a few manufacturers actually make helmets with 'bug screens' in them:
Unfortunately, most of these helmets are rather expensive (most over $100) and many are difficult to purchase because they are made by small European manufacturers…. But they do exist. Some brands, like the Shain and the LAS, have metal bug screens which sounds like a good idea to me in terms of durability of the screen.
After asking about such helmets on a cycling forum, apparently many cyclists just retro-fit their current helmets by buying a small piece of screen and taping it into their helmets or sandwiching the screen between the helmets foam and the outer shell.