The waters in Rio de Janeiro, host of the 2016 Summer Olympics, are teeming with viruses and bacteria from human feces, an investigation by the Associated Press has found.

In some tests, the levels of contamination are up to 1.7 million times what would be considered hazardous on a California beach, according to the AP analysis, which is the first independent testing for both viruses and bacteria at Olympic sites. Brazilian officials and the International Olympic Committee only test for bacteria.

Fevers and stomach problems have already beleaguered some athletes training in Rio, the AP reported. Because most sewage is not treated in Brazil, dangerous waste freely makes its way to bodies of water where Olympians will swim and boat.

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An American expert in waterborne viruses, Kristina Mena, said that the levels found in the waters mean someone would have a 99 percent chance of infection from ingesting a mere three teaspoons of water.

I'd probably skip it.