Why is athlete's foot only found in feet?
Why is athlete’s foot just on the feet? Why do they just live there?”
Chris - Microbes have their own niche. There are certain places on the body where they like to be- they're optimised to grow in those places. Feet are wonderful. They have dead skin which serves as protein, lots of sweat, and it's warm, and it's protected, and it's easy to spread around because you have to put your feet on the ground when you walk about.