The infection comes as Jaysen Carr, a 12-year-old boy from South Carolina, died on July 18 after being exposed to Naegleria fowleri while swimming in Lake Murray. The incident has drawn attention to the dangers of this rare but deadly amoeba that thrives in warm freshwater during the summer.

Missouri health officials are investigating how the person was exposed, but they may have been in the water at Lake of the Ozarks before becoming ill.