The teenager, whose identity has not been released, is receiving care, the North Carolina Department of Health and Human Services said on Thursday. Details on the teen's condition were not provided, but NCDHHS said "once symptoms start, the disease progresses rapidly and usually causes death within about five days."
Officials are still investigating where the teen contracted the amoeba, but Naegleria fowleri can be found in warm freshwater including ponds, lakes and rivers, and it grows best in hotter water, state health officials said.
"The amoeba does not cause illness if swallowed but can be fatal if water with the amoeba in it is forced up the nose into the brain, which can occur by jumping into water, diving, water-skiing or other water activities," NCDHHS said in a statement.
The U.S. usually sees fewer than 10 cases a year of Naegleria fowleri infection, also known as primary amebic meningoencephalitis or PAM, state health officials said.
The first symptoms can be severe headache, nausea, vomiting and fever, and later symptoms include stiff neck, seizures and coma, NCDHHS said.
Earlier this month, an 8-year-old girl in Louisiana, Lillian Smart, died from Naegleria fowleri which she likely contracted while swimming in a lake, her family and state health officials said, according to The Associated Press.
Click here for everything you need to know about Naegleria fowleri.
ABC News' Emily Shapiro contributed to this report.