RIO DE JANEIRO — An investigation by the Associated Press has found high levels of contamination in the waters where Olympians will compete next summer, according to espn.com.

High levels of viruses and bacteria from human sewage were found after independent testing was conducted at the Olympic sites, noted the article. Four rounds of tests were conducted in March, and some competitors have already become sick with fevers, vomiting and diarrhea.

“This is by far the worst water quality we’ve ever seen in our sailing careers,” said Ivan Bulaja, a coach for the Austrian team, in the article. “I am quite sure if you swim in this water and it goes into your mouth or nose that quite a lot of bad things are coming inside your body.”

A sailor, David Hussl, explained in the article that problems have caused him to spend one day in bed, then he cannot sail for two or three days, stated the article.

Most sewage in the region isn’t collected or treated, reported the article. The country’s authorities have pledged to fix the issue, but testing over five months still found water too unsafe for swimming or boating.

“What you have there is basically raw sewage,” said John Griffith, a marine biologist at the independent Southern California Coastal Water Research Project, in the article. “It’s all the water from the toilets and the showers and whatever people put down their sinks, all mixed up, and it’s going out into the beach waters.” He added in the article that if those contamination levels were found in the U.S., it would be shut down immediately.

Brazilian virologist Fernando Spiliki’s tests showed high concentrations of adenoviruses “roughly equivalent to that seen in raw sewage,” noted the article. While locals may have built up immunities to the bacteria over time, tourists and athletes are at risk for illness.

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