The girl contracted the Naegleria fowleri amoeba while swimming in the Brazos River in Texas. It can cause primary amebic meningoencephalitis (PAM), a rare, fatal disease of the central nervous system.

Brazos Bend State Park
Credit: Rajvir Singh/Getty Images

A 10-year-old girl from Fort Worth, Texas died after contracting Naegleria fowleri amoeba, a single-celled organism also known as a "brain-eating" amoeba, while swimming, her family has confirmed. Lily Mae Avant "has gone to be with Jesus," her aunt, Loni Yadon, said in a statement shared on Facebook this morning.

"This past week has been a true testament of the kind of girl she was and the tremendous affect she had on people," Yadon wrote.

On Labor Day weekend, Avant had gone swimming in the Brazos River, which is located near Waco, Texas. It was there that she contracted the amoeba, which is commonly found in fresh water bodies such as ponds, lakes and rivers and in soil, according to the Centers for Disease Control and Prevention (CDC). About a week later, on September 8, Avant came down with a fever, reports NBC Dallas-Fort Worth. That evening, she saw a doctor.

"They got it checked out," her mother's cousin Wendy Scott told the outlet. "There were several viruses going around the school. It was assumed it's a virus because of the symptoms are exactly the same, so she was sent home. She was brought into the emergency room on Tuesday when she woke up unresponsive. She was eyes open, she was there, but she wasn't speaking. Nothing."

Later, Avant was transferred to Cook Children's Medical Center in Fort Worth where doctors did a spinal tap that confirmed she had contracted Naegleria fowleri. She was put into a medically-induced coma while doctors worked to reduce the swelling in her brain.

The night before the girl died, her father John Crawson reportedly spoke at a prayer vigil outside Cook Children's Medical Center and called his daughter "a fighter" and said she's "stronger than anybody I know."

What is Naegleria fowleri?

A spokesperson for the Texas Department of State Health Services told NBC that while the amoeba itself is common, the infection is extremely rare. "We average less than one per year in Texas," an agency spokesperson explained. "However, it is extremely serious and almost always fatal. Since it's so rare, we don't know why a few people get sick while millions who swim in natural bodies of water don't."

Once the organism enters through the nose, it travels to the brain where it can cause primary amebic meningoencephalitis (PAM), a rare, fatal disease of the central nervous system. In very rare instances, Naegleria infections may also occur when contaminated water from other sources (such as inadequately chlorinated swimming pool water or heated and contaminated tap water) enters the nose. You cannot get infected by the amoeba from swallowing water that's contaminated.

Initial "first stage" symptoms include severe frontal headache, fever, nausea, and vomiting, while "second stage" symptoms are stiff neck, seizures, altered mental status, hallucinations, and coma.

It's extremely fatal: Those who are infected generally die within weeks after the symptoms begin, the median being five days. The CDC says that historically, there have only ever been five known survivors of the infection in North America.

How to Prevent Naegleria fowleri Infection

People should always assume there's a low level risk of Naegleria fowleri infection whenever they enter warm freshwater lakes, rivers, and hot springs, especially in southern-tier states, according to the CDC. That said, swimmers might be able to prevent an infection by limiting the amount of water going up the nose (by holding your nose shut, using nose clips, or keeping your head above water) and avoiding water where Naegleria fowleri might live.

For more information, visit the Kyle Lewis Amoeba Awareness Foundation, founded by the family of a 7-year-old who lost his life to PAM in 2010 with the goal of educating and saving lives.