A Texas resident contracted an illness caused by a brain-eating amoeba and died after going for a swim, officials said Wednesday. 

The swimmer developed amebic meningitis infection, which is caused by Naegleria fowleri, more commonly known as a brain-eating amoeba, after swimming in Lake Lyndon B. Johnson in August, according to Austin Public Health. Officials have not publicly identified the victim. 

A sample specimen from the case was sent to the Centers for Disease Control and Prevention, authorities said. 

Naegleria fowleri, a single-celled organism, lives in warm fresh water, health officials said. It enters the body through the nose and travels to the brain. It can cause primary amebic meningoencephalitis, a brain infection that destroys brain tissue. The infection is almost always fatal.

Only 157 cases were reported from 1962 through 2022, according to the CDC. Only four of the patients survived in that period. The agency said in the U.S., most infections have been linked to swimming in southern states. There have been 39 cases of primary amebic meningoencephalitis identified in Texas between 1962 and 2002, according to local officials.

The infection usually occurs in boys younger than 14, according to CDC data. 

There have been several deaths associated with Naegleria fowleri this year, including a Georgia resident and a child in Nevada. Both victims died in July. The Florida Department of Health also reported an infection in March. 

Symptoms start one to 12 days after swimming or having some kind of nasal exposure to water containing Naegleria fowleri, according to the CDC. People die one to 18 days after symptoms begin. 

Signs of infection include nausea, vomiting, fever, a severe headache, stiff neck, seizures, altered mental state and hallucinations. Some who are infected can go into a coma. 

“Although these infections are very rare, this is an important reminder that there are microbes present in natural bodies of water that can pose risks of infection,” Austin-Travis County Health Authority Dr. Desmar Walkes said. “Increased temperatures over the summer make it ideal for harmful microorganisms to grow and flourish.” 

Naegleria fowleri occurs naturally in the environment, so swimmers should always assume there’s a risk when they enter warm fresh water, health officials said. It does not live in saltwater, but Naegleria fowleri can be found in swimming pools or water parks that are poorly maintained or minimally chlorinated

Austin Public Health noted that to reduce the risk of amebic infections, swimmers should limit the amount of water going up their nose by holding their nose shut, using nose clips or keeping their heads above water when in freshwater. 

Swimmers and boaters should avoid jumping or diving into bodies of warm fresh water, especially during the summer, according to the CDC.