Following a hot summer, experts are warning swimmers about a dangerous brain-eating amoeba native to Florida freshwater bodies of water.
Florida's warm lakes and ponds are thriving places for the amoeba Naegleria fowleri, which can cause primary amebic meningoencephalitis (PAM), a rare and very fatal infection.
While infections are infrequent, a Louisiana resident died last month due to a Naegleria infection, according to the Louisiana Department of Health.
The girl was identified by local media as 8-year-old Lillian Smart.
"The resident most likely acquired the infection while swimming in Lake Claiborne, located in Claiborne Parish, shortly before illness," according to a press release by the Louisiana State Board of Medical Examiners.
There have only been 173 Naegleria infections in the last 88 years in the U.S., but exposure to the amoeba has a 97% mortality rate, according to the Centers for Disease Control and Prevention. Naegleria infections occur when water enters through a person's nose. The amoeba thrives on nutrients found in neurotransmitters in a person's nasal cavity and in the brain. Infections do not occur from drinking the water.
From 2012-2021, there were 31 infections in the U.S. overall, but 3 were fatal.
From 2012-2021, there were 31 infections in the U.S. overall, but 3 were fatal.
"It's one of those diseases that we consider to be a low prevalence, and there is not a lot of information that can help," said Dr. Jose Alexander is the executive director of microbiology at AdventHealth in Central Florida. "Sadly, this is one of the diseases that we know that a lot of the records that we have have been diagnosed postmortem."
According to the Florida Department of Health, PAM symptoms can be mild at first but can worsen quickly and include severe fever, neck pain, nausea, and vomiting.
Naegleria is only active when lakes and ponds have a temperature of 80 degrees or more. But that seems to be changing, with intense heat beyond August becoming a more common occurrence, Alexander said.
"We know that now we have more days, more warmer days across the year; water is warmer, the amoeba is more active," he said. "We also have cases in places of the U.S. that we thought that the amoeba probably wouldn't be able to be so active or even infections in the north where we have bodies of water that are very cold."
Naegleria is native to Florida's fresh bodies of water. It tends to live in the sediment. The Florida Department of Health advises not kicking up the mud in lakes or ponds, as it can stir up Naegleria.
It also advises wearing nose clips to prevent the amoeba from traveling up the nasal cavity.
If someone is infected, it can take between three to seven days to die, according to AdventHealth. It can also take six days to test for Naegleria. However, Alexander and an AdventHealth team developed a lab test in 2022 that can detect the amoeba in spinal fluid within a few hours.
"We can perform that test in-house, and that is a quick, rapid diagnostic for guiding therapy," he said.
The test is very sensitive and effective, but prevention is the best medicine, Alexander said.
"If you're getting into the lake, protect your face, protect your nose, or use a nose clip. I think that's the best way to protect ourselves."
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