Health officials in Missouri confirm a case of a rare bacterial “brain-eating” infection in an adult.

Officials from the Missouri Department of Health and Senior Services have confirmed the case through laboratory testing. The unidentified patient is being treated in an intensive care unit for Naegleria fowleri. The organism is a single-celled amoeba that can cause a deadly brain infection known as Primary Amebic Meningoencephalitis or PAM. Officials are still investigating the source of the infection, but say the patient had gone water skiing at the Lake of the Ozarks just days prior to becoming ill.

PAM is an extremely rare condition. In the United States, only 167 cases have been reported since 1962. People can reduce the risk of infection by limiting the amount of water going up the nose.