Brain-Eating Amoeba Strikes Again, This Time in Minnesota

This is Naegleria fowleri, the so-called brain-eating amoeba. Francine Marciano-Cabral

A teenage boy became gravely ill this week after swimming in a lake in west-central Minnesota. Several media outlets have reported that he is suffering from primary amebic meningoencephalitis (PAM), which is caused by the so-called brain-eating amoeba.

While it's not rare to hear about this infection in the summer months of July and August—a California woman died of the condition last week, and it strikes up to eight people per year in the United States—it is unusual to hear about cases occurring so far north. Before now, only two cases of PAM have ever been reported north of Missouri.

This parasite, known as Naegleria fowleri, is usually found further to the south, as it thrives in warm waters. People get the infection when they get water way up into their nasal passages, usually when swimming in lakes in July and August, when temperatures are highest. From there, the protozoan can reach the brain and begins to wreak havoc. The first American case of PAM acquired from tap water was recorded in Louisiana in July 2013.

According to the Minnesota Health Department, the boy, 14-year-old Hunter Boutain, was swimming last Tuesday in Lake Minnewaska in Pope County.

The warmth-loving microbe is limited by climate yet appears to be spreading, as temperatures have risen in parts of the United States, says Jennifer Cope, a medical epidemiologist for the U.S. Centers for Disease Control in Atlanta. That said, there hasn't been an increase in the number of cases in recent years.

While Naegleria fowleri infections are rare, they are quite deadly: Of the 134 people who have been diagnosed with PAM since 1972, only three have survived. One 12-year-old Arkansas girl made a complete recovery from the condition in 2013.

Brain-Eating Amoeba Strikes Again, This Time in Minnesota | Tech & Science