A teenage boy who developed a rare brain infection after swimming in a western Minnesota lake has died.

In a statement issued through the University of Minnesota Medical Center, the family of Hunter Boutain, 14, of Alexandria, says his condition deteriorated through the night and he was declared brain dead Thursday morning.

A spokesman for the University of Minnesota Masonic Children's Hospital confirmed the boy's death.

“I thank you all for praying for Hunter,” the teen’s brother Lee Boutain posted on Facebook. “The Lord didn’t want him to stay on earth. As much as I am hurt I know I can’t love him as much as God.”

State and federal health officials have been working to confirm whether Hunter's infection was the result of a water parasite that's more common in warmer southern states. He became ill after swimming in Lake Minnewaska.

Minnesota Public Radio reports the case has officials puzzled because it happened in a bigger lake than the two previous cases amid a cool summer.

The parasite was confirmed in the deaths of two children who became infected in Lily Lake in Stillwater, in 2010 and 2012. The infection had never been found so far north before.

While the amoeba is common, officials say the risks of infection are extremely low.

The Associated Press contributed to this report.