Doctors believe Zachary Reyna, 12, contracted the rare amoeba Naegleria fowleri while kneeboarding with friends in a shallow ditch near his house. The parasite breeds in shallow, warm freshwater and is generally harmless unless ingested nasally, after which it travels to the brain and kills 99 percent of those who contract it.
"The battle is over for Zac but he won the war," a family-updated Facebook page said Saturday. Reyna was scheduled to be removed from a ventilator once his organs had been harvested for donation, CNN said.
"Even though Zac has passed, he will still be saving many lives," this new post said.
Reyna is the second child this summer to contract the extremely rare parasite. From 2001 to 2010 there were only 32 reported cases brain infections caused by Naegleria fowleri. Of them, nearly everyone died.
Everyone except for Kali Hardig of Arkansas, who contracted the parasite at a water park earlier this summer and was given an experimental drug that successfully warded off the infection. She is one of only three known survivors of the infection in the last 50 years.
Doctors said they tried the same treatment on Reyna unsuccessfully.