A visitor from Missouri is in the ICU after contracting a brain-eating parasite in Iowa. The potentially fatal amoeba is called Naegleria fowleri, and it enters its host through the nose, often when swimmers dive or jump into warm freshwater. The infected person had gone swimming at the Lake of Three Fires State Park in southwest Iowa.

NBC News reports the state park’s beach has been closed for swimming after the infected person went to the hospital to be treated. Symptoms of  Naegleria fowleri include fever, vomiting, and seizures, among other issues. The microbe feeds on brain tissue leading to swelling and then, death. The Iowa Department of Public Health is testing the waters at the state park, while the Missouri Department of Health and Senior Services is monitoring the hospitalized swimmer. It’s the first confirmed case of a Missouri resident being infected by the brain-eating amoeba in 35 years. 

“These situations are extremely rare in the United States and in Missouri specifically,” said Dr. George Turabelidze, Missouri state epidemiologist in a press release. “But it’s important for people to know that the infection is a possibility so they can seek medical care in a timely manner if related symptoms present.” 

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According to the Centers for Disease Control and Prevention, the amoeba is relatively common, especially in warmer southern waters, but contracting the infection is unusual. Only 31 cases were reported in the last decade in the U.S. Most of those cases were contracted at swimming holes, while two occurred after nasal cleansing with contaminated tap water, and one case involved a backyard slip-n-slide. There were 154 confirmed cases of the infection on record from 1962 to 2021. Only four of those people survived. The fatality rate is estimated to be over 97 percent. The amoeba is not contagious.