Lake Mead brain-eating amoeba death is one of few in US

The death of a Las Vegas-area teen from a rare brain-eating amoeba that researchers believe he was exposed to in the warm waters of Lake Mead should prompt caution, not panic, among people in lakes, rivers and freshwater springs, experts said Friday.

“It catches people’s attention because of the name,” former public health epidemiologist Brian Labus said of the naturally occurring organism officially named Naegleria fowleri, but more often than not nicknamed the brain-eating amoeba. “But it’s a very, very rare disease.”

The federal Centers for Disease Control and Prevention has counted only 154 cases of infection and death from amoeba in the US since 1962, said Labus, who teaches at the School of Public Health at the University of Nevada, Las Vegas. . Nearly half of those cases were in Texas and Florida. Only one was reported in Nevada prior to this week.

“I wouldn’t say there’s an alarm going off for this,” Labus said. “People have to be smart about it when they find themselves in places where this rare amoeba actually lives.” The organism is found in waters ranging from 77 degrees Fahrenheit (25 Celsius) to 115 degrees (46 C), he said.

The Southern Nevada Health District did not identify the teen who died, but said he may have been exposed to the microscopic organism over the weekend of September 30 in the Kingman Wash area on the Arizona side of the Colorado River reservoir. behind the Hoover Dam. The district published the case Wednesday, following confirmation of the cause by the CDC.

The district and the Lake Mead National Recreation Area, which oversees the lake and Colorado River, noted that the amoeba only infects people by entering through the nose and migrating to the brain. It is almost always fatal.

“It cannot infect people if ingested, and it does not spread from person to person,” the news releases from the two agencies said. Both advised people to avoid jumping or diving into warm bodies of water, especially during the summer, and to keep their heads above water in hot springs or other “untreated geothermal waters” that collect in small canyons in the vast area. recreational.

“It’s 97% fatal but 99% preventable,” said Dennis Kyle, a professor of infectious diseases and cell biology and director of the Center for Global Tropical and Emerging Diseases at the University of Georgia. “You can protect yourself by not jumping into water that goes up your nose, or by using nasal packing.”

The amoeba causes primary amoebic meningoencephalitis, a brain infection with symptoms similar to meningitis or encephalitis that initially include headache, fever, nausea, or vomiting, and then progress to stiff neck, seizures, and coma that can lead to death. .

Symptoms can begin one to 12 days after exposure, and death usually occurs within about five days.

There is no known effective treatment, and Kyle said a diagnosis almost always comes too late.

Kyle, who has studied the organism for decades, said the data did not immediately suggest that waters warmed by climate change affected the amoeba. He said that he knew of fewer than four cases in the entire country.

A news survey found cases in northern California, Nebraska and Iowa. A CDC map showed most cases over the past 60 years in southern US states, led by 39 cases in Texas and 37 in Florida.

“I think this year is kind of the average year for cases,” Kyle said. “But this was a very hot summer. The key point is that warmer weather tends to bring more amoebas into the environment.”

Not many labs regularly identify the organism, Kyle noted. He said that AdventHealth Central Florida recently joined the CDC with programs capable of identifying you.

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