'Brain-Eating Amoeba' on the Loose in Fresh Water Lakes

Before you go jump in the lake, there could be a deadly organism lurking at the bottom of your favorite watering hole.

Health experts are warning of a freshwater-dwelling organism known as Naegleria fowleri, commonly referred to as the “brain-eating amoeba.”

The deadly bug can be picked up in warm freshwater lakes, usually when swimmers get water up their nose, causing a burning sensation and sometimes sneezing. But the danger isn’t always over when the discomfort goes away.

Naegleria fowleri under a microscope. | Center for Disease Control and Prevention

The brain-eating amoeba is believed to be responsible for the recent death of an 18-year-old Ohio teen after a white rafting trip in North Carolina.

The amoeba, present in freshwater across the United States, causes primary amebic meningoencephalitis (PAM), a condition in which the covering of the brain and spinal cord swell due to the infection. The organism travels through the nose up the nerve tissue and into the brain. There, the organism is nourished by the brain, eventually causing the destruction of the brain tissue.

Symptoms of the infection appear five days after nasal exposure to the organism and may include headache, nausea, vomiting and fever. Infection does not occur from drinking contaminated water but from nasal ingestion. Death occurs up to 18 days after symptoms begin.

According to the Centers for Disease Control and Prevention, the U.S. faces between zero and eight cases of parasitic amoeba infections every year, with 37 registered from 2006-2015. Although rare, almost every case is fatal.

“The amoeba is found in warm to hot fresh water including lakes, rivers and hot springs. It seems that large lakes, such as Lake Michigan, aren’t affected by this bug, since the organism likes hot water, which tends to only be in smaller bodies of water,” says Brian Walesa, director of Epidemiology and Infection Prevention at Advocate Christ Medical Center in Oak Lawn. “Most cases occur in the South, although more recent cases have been reported in Minnesota and Ohio.”

Although unlikely, Walesa says the infection is frequently related to water sports.

“On top of that, the organism lives in the sediment, on the floor of these water sources, so kicking up sand or swimming deeper could be additional risk factors,” he says.

There is no cure for amebic meningoencephalitis, but the CDC suggests keeping your head above water and using a nose clip or holding your nostrils shut with your hands while swimming and participating in other water activities.

“Of course, the only foolproof way to keep from becoming infected is to avoid water-related activities in warm freshwater,” Walesa says.

Meningoencephalitis itself is not currently reportable, as there are many causes. However, specific organisms causing this may be reportable, including PAM, says Melaney Arnold, spokeswoman for the Illinois Department of Public Health.

“IDPH has never has a case of PAM reported,” Arnold said.

Source: Advocate Christ Medical Center