The Associated Press commissioned a study of the virus and bacteria levels in the waters where Olympic athletes will compete next year in Rio de Janeiro. The testing found dangerously high levels of pathogens from human sewage waste.
Five things to know about the AP testing:
In the three water venues for Olympic games, the tests found levels of human adenovirus roughly equal to that seen in raw sewage. Global water experts who examined AP's data said the water is not safe for swimming or boating.
RISK FOR ATHLETES
A risk assessment conducted for the AP by a U.S. expert said athletes who ingest just three teaspoons of water (16 milliliters) have a 99-percent chance of being infected by a virus. It is not known what percentage would actually fall ill.
While bacterial tests of Rio's water were better than viral analyses, some of the AP tests found levels of bacterial pathogens (fecal coliforms) spiking in the lake to 10 times above the Brazilian limit for secondary contact (boating/rowing) and 18 times the limit in the Marina da Gloria in one sample.
Brazilian officials monitoring water quality do not check for these viral levels — despite the fact that water quality experts say the majority of waterborne illnesses are viral in nature.
IMMUNITY FOR SOME
Brazilian health experts who deal with sewage-related illnesses point out that most Brazilians develop immunities to these viruses by the time they reach adolescence, but foreigners won't have that advantage. The doctors all classified Rio's public health situation as having "endemic" problems related to sewage-polluted waters.