I heard urine is actually sterile when it first comes out. So is perspiration. It only becomes germy when bacteria in the air is exposed to it. But doesn't poop (of any living thing) have E-Coli bacteria in it?
Urine should be sterile when it exits and it has a mild anti-bacterial quality. That is why it was use to rinse wounds of injured solders in the old days. It quickly becomes non-sterile however upon contact with other surfaces. It don't know how sweat could be sterile, as it exits through pores in the skin and would become contaminated as it exits from skin flora.