After Louisiana Girl's Death From Brain-Eating Amoeba, Here's Who Faces the Highest Risk This Summer

An 8-year-old Louisiana girl has died after contracting a rare and almost always fatal brain-eating amoeba while swimming, prompting renewed questions from families about who faces the greatest risk from the pathogen and how to reduce exposure during the remaining weeks of summer.

Lillian Smart, of Ruston, Louisiana, died Aug. 22, according to a public Facebook post shared by her family on the "Love for Lillian" page, which said the "injuries to her brain were too severe for her little body to recover from." The Louisiana Department of Health reported Aug. 19 that it had confirmed a case of Naegleria fowleri, commonly known as a brain-eating amoeba, which Smart likely contracted while swimming in Lake Claiborne.

Naegleria fowleri is commonly found in warm freshwater lakes, rivers, canals and ponds throughout the United States, according to USA Today. It is not found in saltwater, and properly maintained and chlorinated swimming pools do not harbor the organism. The amoeba has earned its "brain-eating" nickname because it can cause a rare but devastating infection called primary amebic meningoencephalitis, or PAM, which destroys brain tissue and is almost always fatal.

Infection occurs when water containing the amoeba forcefully enters a person's nose, typically during activities such as diving, jumping or swimming underwater in warm freshwater. Naegleria fowleri cannot infect people if swallowed, and the infection does not spread from person to person, meaning the risk is tied specifically to water entering the nasal passages rather than any other form of exposure or contact with an infected individual.

Once inside the nasal cavity, the amoeba's path to the brain reflects a specific and unusual biological behavior. "Naegleria fowleri is a harmless pond dweller – unless it ends up in the nose of a human swimmer," according to a research article published in the journal Science. "Once inside, the amoeba can crawl along nerve fibers in the nasal cavity and through little openings in the skull until it reaches the brain."

Scientists have not fully determined why the organism, which normally feeds on bacteria in its natural freshwater environment, exhibits this dangerous behavior once it enters a human host, though researchers believe it may be connected to the amoeba's natural tendency to crawl into narrow spaces while searching for food. Katrina Velle, a cell biologist at the University of Massachusetts Dartmouth, described the infection as an unfortunate consequence of the organism simply following its evolved instincts. "It's really just an unfortunate circumstance when the amoebae get into your upper sinuses," Velle told Science. "They're just doing what they've evolved to do − looking for nooks and crannies where their bacteria should be."

Despite the infection's severity, brain-eating amoeba cases remain extremely rare. The organism typically kills fewer than 10 Americans each year, according to the Centers for Disease Control and Prevention. Of the 167 confirmed cases recorded in the United States between 1962 and 2024, only four people have survived the infection, underscoring both its rarity and its near-uniform lethality once symptoms develop.

Lillian's death is not the first pediatric case reported in recent years involving swimming in a natural freshwater setting. In July 2025, a boy died from the brain-eating amoeba after swimming in a lake in South Carolina, according to earlier USA Today reporting, reflecting a recurring pattern in which warm-weather freshwater recreation during summer months has periodically produced isolated but devastating cases across different states.

While no method can completely eliminate the risk of exposure during summer water activities, public health officials have identified several practical steps that can meaningfully reduce the likelihood of the amoeba entering a swimmer's nasal passages. Wearing a nose clip or holding one's nose before diving or jumping into freshwater can help prevent water from being forced up into the nose during entry. Avoiding digging or stirring up sediment in shallow water is also recommended, since the amoeba is more likely to be concentrated in that shallow, warmer sediment layer near the bottom of lakes and ponds. Additionally, keeping one's head above water while in hot springs, where warmer water temperatures can support the organism's growth, is advised as a further precaution.

The rarity of Naegleria fowleri infections means that public health experts generally do not advise avoiding freshwater swimming altogether, given how statistically uncommon the infection is relative to the millions of people who swim in lakes, rivers and ponds across the country each summer without incident. Instead, the recommended precautions focus specifically on reducing the likelihood that water containing the amoeba reaches the nasal passages during the specific moments of highest risk, such as diving, jumping into water, or engaging in activities that stir up bottom sediment in warm, stagnant or slow-moving freshwater environments.

Health officials in Louisiana have not indicated whether additional cases tied to Lake Claiborne specifically have been identified beyond Smart's confirmed infection, and the state health department's Aug. 19 announcement did not detail any broader public health advisory regarding continued recreational use of the lake. As is standard practice following confirmed Naegleria fowleri cases, state and local health officials typically continue monitoring affected water bodies and may issue additional public guidance if warranted, though such infections are generally treated as isolated environmental exposures rather than indicators of an ongoing outbreak, given the organism's naturally widespread presence in warm freshwater environments nationwide.

As families continue enjoying freshwater recreation during the final weeks of summer, Smart's death serves as a somber reminder of the rare but serious risk associated with warm freshwater exposure, even as public health officials emphasize that the infection remains exceedingly uncommon and that basic precautions, including nose clips and avoiding shallow-water sediment disturbance, can meaningfully reduce, though not entirely eliminate, the already low statistical risk most swimmers face each season.