Researchers have confirmed that the death of a 4-year-old Louisiana boy was caused by a microorganism called Naegleria fowleri, which digests neural tissues.
The boy, Drake Smith Jr., spent most of a day in July 2013 playing on a slip ‘n slide. Nine days later he experienced severe headaches, vomiting and developed a 104-degree fever. He died of an infection called primary amebic meningoencephalitis (PAM), brain swelling caused by the single-celled organism. PAM is almost always fatal.
N. fowleri is usually found in freshwater systems, such as lakes. Most of the time, it is not a threat to municipal water systems or swimming pools because they are normally disinfected with chlorine or other substances that kill the organism.
A study published in this month’s journal Clinical Infectious Diseases stated that Smith’s case is the first in which an individual acquired the infection from tap water.
For the brain-eating amoeba to make its way to a person’s brain, it must enter the nose, after which it penetrates the bone between the sinuses and brain and then breaks down nerve cells. Drinking water with N. fowleri wouldn’t be enough to cause an infection.
“[The boy] spent all day on the slide,” said Raoult Ratard, Louisiana’s state epidemiologist, according to National Geographic. “I wouldn’t be surprised if some water went up his nose.”
Some experts say this particular incident may be linked to unsafe water conditions and damaged systems that came about after Hurricane Katrina hit in 2005.
“St. Bernard was under 15 feet of floodwater,” said Jake Causey, chief engineer for the Louisiana Department of Health and Hospitals, according to National Geographic. “Water pipes were broken, and the [water] pressure was zero.”
The town’s population fell to about 35,000 from approximately 67,000, leaving many empty buildings where water sat in the sun for some time. Ratard said studies have revealed that summer heat can eliminate chlorine added to municipal water. Without it, N. fowleri would multiply, he said.
Samples acquired from Smith’s home were tested by the Centers for Disease Control and Prevention and showed traces of N. fowleri contamination.
“The same [strain] of N. fowleri that was found in the child’s brain tissue was found in the hose and in the water from the faucet in the yard,” Ratard told National Geographic.
Other scientists, however, say proving a definite linkage between Hurricane Katrina and the microorganism will be difficult.
“My understanding is that this amoeba is pretty common in freshwater throughout the United States. As a scientist, I wouldn’t necessary support Katrina as a causation there,” Dawn Wesson, an epidemiologist at Tulane University in New Orleans, according to National Geographic. Wesson was not involved in the investigation.
Other studies are delving into how N. fowleri becomes infectious.
“This is a free-living amoeba that doesn’t have to infect anybody, it’s perfectly happy feeding on bacteria,” Francine Marciano-Cabral, a microbiologist at Virginia Commonwealth University who is studying the microorganism, told Newsweek. “What we want to find out is why in some people it is so pathogenic and deadly and what makes it that way?”
Two other Louisiana residents were reported to have contracted and died of PAM following the use of neti pots, which flush the sinuses with salty water. One of these incidents also took place in St. Bernard Parish.
(With reports from National Geographic and Newsweek)
