When it comes down to it, one of the major life-enhancing aspects of modern civilization is the fact that it has removed a lot of poop from our daily life. For most of humanity's existence people's hygienic habits were, in some respects, a little gross. When humans were all just hunter-gathers who nomadically moved around, sanitation took care of itself as people did not literally sit in their own stuff. When agriculture and farming--unmitigated technological advances--were developed people become more stationary as they began growing crops and raising livestock. This scenario created a condition in which people lived amongst their own sewage.
Sanitation, outhouses, and plumbing, in essence, allow there to be some separation where a person ate, slept, and lived from where they did their...other business. Gone are the bed pans and cesspools that littered the cities of the 18th and 19th century in which being a "night soil man" was a real career.
Now, anytime we hear of a raw sewage exposure in a, for example, recreational waterway it is major news. The 21st Century human has no tolerance for a feces-filled life (though we still are exposed to feces in everyday life all the time, just much more surreptitiously).
However, the world's elite athletes are literally poised to be swimming in it, quite literally, if Rio's waterways remain as feces-ridden as they currently are at the time of the Olympics. Viral counts are extremely high in some of the waters tested.
In prior Olympics blood-doping involved increasing the oxygen delivery capacity of the blood, in 2016 a blood-doper will be someone whose blood carries the requisite antibodies and levels of antibiotics to excel in a river of poop.