Arkansas girl Kali Hardig battles brain-eating amoeba

A 12-year-old Arkansas girl is in critical condition after contracting a rare but deadly brain-eating amoeba.

Kali Hardig is thought to have contracted the rare form of meningitis, known as primary amoebic meningoencephalitis, from a sandy-bottomed lake at Willow Springs Water Park in Little Rock, according to the Arkansas Department of Health.

She was admitted to Arkansas Children's Hospital about eight days ago.

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The infection is caused by a microscopic amoeba called Naegleria fowleri, which enters the body through the nose and travels to the brain.

It's usually found in people who have been swimming in warm freshwater.

While exceedingly rare, Naegleria fowleri infections are almost always fatal. Just one of the 128 people infected in the United States since 1962 has survived, according to the Centers for Disease Control and Prevention.

The first symptoms appear one to seven days after infection by the amoeba, including headache, fever, nausea, vomiting and a stiff neck, according to the CDC.

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The 85-year-old water park in Little Rock was also linked to a Naegleria infection in 2010.

It is now closed at the state's request, according to the Arkansas Department of Health.

“Swimming is a healthy summertime activity, and we do not want to discourage people from swimming,” state epidemiologist Dirk Haselow said in a statement. “If concerned about Naegleria, avoid swimming, diving or other activities that push water up the nose, especially in natural waters when temperatures are high and water levels are low.”