CHARLOTTE -- The U.S. National Whitewater Center shut down all whitewater activities Friday, after tests from the Centers for Disease Control confirmed brain-eating amoeba were found in the water.

Those preliminary tests found the amoeba in a majority of the 11 water samples taken from the facility, Mecklenburg County Health Director Dr. Marcus Plescia said.

We first learned about the deadly amoeba earlier this week when 18-year-old Lauren Seitz of Ohio died after being infected. 

The Whitewater Center will now work with the health department to figure out how, in addition to the treatment systems already in place, they can reduce the concentration of the amoeba in the water.

"Trying to reach a state where you can't detect this microorganism, which is incredibly prevalent and which is found in most open water sources, is very difficult," Plescia said. 

Until they find a solution, whitewater activities will remain closed. All other outdoor activities will stay open.

Even with the outcome of these results, Plescia said the risk of infection from the amoeba is very low.