You probably already know that traveling can be hazardous to your health, particularly when it comes to picking up those nasty little respiratory and gastrointestinal viruses that are spread via shared surfaces on planes, hotels and restaurants. (If you don't know this, you're either hopelessly out of touch, or blissfully unaware.)

But it gets worse: Now there's evidence that it's not just colds and flu that business travelers have to fear.