The World Health Organization has asked the IOC to analyze virus levels in Rio de Janeiro's Olympic waters, and the governing body of world sailing says it will start doing its own independent virus tests.
The moves come after an Associated Press investigation showed a serious health risk to Olympic athletes in venues around Rio rife with sewage.
In a statement to the AP, the World Health Organization said it suggested the International Olympic Committee start monitoring for viruses at the Rio venues.
"WHO has also advised the IOC to widen the scientific base of indicators to include viruses," the statement said. "The risk assessment should be revised accordingly, pending the results of further analysis. The Rio Local Organizing Committee and the IOC are requested to follow WHO recommendations on treatment of household and hospital waste."
A spokesman from the Rio organizing committee referred comment to the IOC, which is meeting in Kuala Lumpur, Malaysia.
Olympic organizers and the Brazilian government have tested only for bacteria to decide if the water is safe. Many experts say viruses are a far bigger problem and need to be monitored.
The International Sailing Federation said independently it would start testing for viruses.
"We're going to find someone who can do the testing for us that can safely cover what we need to know from a virus perspective as well as the bacteria perspective," Peter Sowrey, chief executive of the ISAF, said. "That's my plan.
