I am sick a 2-3 times a year. The last couple of times I've been sick the symptoms have been the same: runny nose, fever, exhaustion; just a bad cold / flu. But there is a pattern, every single time I get sick, it has occurred directly after a period of time where I was depriving myself of sleep. Last spring, I went almost 2 weeks with less than 5 hours of sleep. It resulted in me getting this flu thing. The same thing happened in the fall, and now it's happened again. Sometimes I wonder ...