An eight-year-old Louisiana girl has died after contracting a rare, typically fatal brain-eating amoeba after a swim in Lake Claiborne.

Lillian Smart, of Ruston, died on Saturday, one day after celebrating her birthday, her family announced in a public Facebook post on the “Love for Lillian” page.

“Last night Lillian ran from our arms to the arms of Jesus,” her family said in the post. “The injuries to her brain were too severe for her little body to recover from. Everyone did everything they could to keep her here. We are heartbroken and honestly do not know what to do next. How do we put one foot in front of the other without our girl?”

The Louisiana department of health confirmed on 19 August that a state resident had been infected with Naegleria fowleri and said the exposure most likely occurred while the person was swimming in Lake Claiborne in Claiborne parish. Family friends later identified Lillian as the infected resident, according to reports from several local media outlets.

Naegleria fowleri infections are almost always fatal.

Lillian had been hospitalized since 15 August, KNOE reported. As her family faced the crisis, more than two dozen businesses in Ruston showed support and donated a portion of sales to the Smart family, according to the Facebook page.

Naegleria fowleri infections are extremely rare, with only a handful occurring in Louisiana since 2011.

The amoeba flourishes in warm water and is most commonly found in southern states during the summer. Only about 180 cases have been identified in the US since 1937, according to the Centers for Disease Control and Prevention.

In 2023, an Arkansas child died after contracting Naegleria fowleri from a country club splash pad in the state capital of Little Rock.

Naegleria fowleri can be found in warm freshwater across the country, including lakes, rivers and ponds. It is not found in salt water or in swimming pools that are properly maintained and chlorinated.

Experts say the climate crisis is causing the amoeba to pop up in parts of the US where it isn’t typical, such as the north and west. It is likely to cause primary amebic meningoencephalitis, a brain infection that can develop when contaminated water enters the nose and the amoeba travels to the brain.

People cannot become infected just by swallowing water containing Naegleria fowleri, and the infection does not spread from one person to another.