CHARLOTTE, N.C. – Chlorination and filtration systems were inadequate at the U.S. National Whitewater Center, where a rafter became infected with a deadly amoeba, a federal health official said Thursday.

Dr. Jennifer Cope of the Centers for Disease Control and Prevention said results of all 11 water samples taken at the centre detected the presence of an amoeba that infected and killed an Ohio teenager who had rafted at the centre, The Charlotte Observer reported (http://bit.ly/297YeHW). Lauren Seitz had visited the centre in Charlotte with a church group and died June 19.

Speaking by teleconference, Cope called the results “significant” and at levels the CDC had not previously seen.

The centre has suspended whitewater rafting and kayaking, but other activities continue at the facility.

On its website, the centre said it will drain all the water from its whitewater channels to dry them, clean all concrete and rock in the channels, and test both its wells and city water supply for the amoeba. The statement also said the centre will work with the CDC, health officials and other professionals to decide on water quality measures to minimize amoeba risks. The centre said it does not expect to eliminate the amoeba risk.

State lawmakers are backing legislation that would make it easier for health officials to regulate such centres.