A beach in Iowa is closed after a rare life-threatening infection of the brain was confirmed in a visitor who recently went swimming there.The beach at Lake of Three Fires State Park in Taylor County will be closed temporarily to swimmers, the Iowa Department of Public Health said Friday."The closure is a precautionary response to a confirmed infection of Naegleria fowleri in a Missouri resident with recent potential exposure while swimming at the beach," according to a release from the health department.Naegleria fowleri is a "microscopic single-celled free-living amoeba that can cause a rare life-threatening infection of the brain called primary amoebic meningoencephalitis (PAM)," said the agency. "PAM is extremely rare. Since 1962, only 154 known cases have been identified in the United States," the release said.Naegleria fowleri is commonly found in soil and in fresh warm water such as lakes, rivers and hot springs, according to the U.S. Centers for Disease Control and Prevention. It can also be found in poorly maintained or unchlorinated pools.Infections caused by Naegleria fowleri may occur when water, where the amoeba is present, enters the body through a person's nose, then travels up to the brain where it destroys brain tissue, the health department said. The infection isn't contagious and can't be caused by swallowing contaminated water.The health department is working with the CDC to test the lake water and "confirm the presence of Naegleria fowleri," which will take several days, the release said.No additional suspected cases are currently being investigated in Missouri or Iowa, the agency said.Although rare, PAM is "devastating" and "usually fatal," according to the CDC. "Among well-documented cases, there are only five known survivors in North America," the CDC said.In September 2021, a child in North Texas died after contracting the rare brain-eating amoeba at a city splash pad. In 2020, a 6-year-old boy in Lake Jackson, Texas, died after exposure to the amoeba that was found in the water of splash fountain where he had played.A 10-year-old Texas girl died in 2019 after battling the brain-eating amoeba for more than a week. Symptoms begin with severe headaches, fever, nausea, and vomiting before escalating to seizures, hallucinations, and a coma, according to the CDC.It takes about five days after infection for initial symptoms of primary amoebic meningoencephalitis to show up, according to the CDC. The disease progresses rapidly and usually causes death between one and 18 days after symptoms begin.To reduce the risk of infection, the health department advises swimmers to limit how much water goes up their nose by holding their nose shut or using nose clips, keeping their head above water, and avoiding being in the water when temperatures are very high.