In 2010, 7-year-old Annie Bahneman died of a rare brain-eating amoeba after swimming in Stillwater, Minnesota's, Lily Lake. Two years later, 9-year-old Jack Ariola Erenberg died of the same infection after swimming in the same lake.

Both deaths were attributed to Naegleria fowleri, a parasite that lives in warm freshwater and is harmful when it enters the human body through the nose. Infections usually occur during long periods of hot weather, resulting in lower water levels and high water temperatures.

Recent weather conditions led officials from Washington County’s Department of Public Health & Environment on Thursday, July 29,to issue a warning about the risks of Naegleria fowleri when swimming.

“Current conditions are exactly what we worry about with warm, shallow and stagnant waters,” said Lowell Johnson, the department’s director. “We hope this reminder will help prevent future infections as families seek relief from the heat this summer.”

Between 1962 and 2019, 148 infections were reported in the United States, mostly in the South. Only four people survived.

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Infections generally increase during heat waves because Naegleria fowleri is a heat-loving organism that grows best at higher temperatures up to 115 degrees, according to the Centers for Disease Control and Prevention.

The official cause of death for Annie and Jack was primary amebic meningoencephalitis, also called PAM.

Washington County officials said swimmers can reduce the risk of PAM by limiting the amount of water going up the nose. When taking part in water-related activities in bodies of warm freshwater, swimmers should hold their noses shut or use nose clips, keep their heads above water and avoid digging or stirring up sediment.

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