MI's point was completely missed. While swapping spit is normally safe, an infection is easily noticeable, like herpes, and can be transmitted while the person is infectious. Similarly, piss drinking is also normally safe. However a UTI, which can be much harder to detect, or maybe even an open sore from an STD, could cause an infection in the drinker if they get it in an eye, or abrasion. WI's main point that advertising it as completely sterile implies there are no risks at any point.