The Florida Department of Health warned people against warm, shallow waters after Zachary Reyna contracted primary amoebic meningoencephalitis, caused by the rare single-celled parasite Naegleria fowleri, while playing in a ditch by his house in LaBelle on August 3.
Zachary's mother took him to the hospital after he slept all day the next day, unusual behavior for an active 12-year-old boy. Surgeons operated on his brain and diagnosed him with PAM, which destroys brain tissue and is nearly always fatal.
But there's hope for Zac, and for 12-year-old Arkansas girl Kali Harding, who contracted the parasite a few weeks ago but has responded positively to an experimental anti-amoeba drug.
The Centers for Disease Control released some of the same anti-amoeba drug used to treat Kali to Zac's doctors.
Through 2012, there were 128 known cases of Naegleria fowleri-caused infections, and just two survivors. The infection typically presents within seven days and kills within 12, so Kali and Zac and their families are optimistic about doubling the survival rate.
"We continue to be amazed by Kali's progress," her family said in a statement Thursday. "Today she's able to sit up on her own, write some words on a white board and stand with assistance for very brief stretches. She's even able to throw and catch a ball with her therapists. We are grateful for the continued prayers from Kali's supporters, which no doubt drive her recovery."
Kali's doctors treated her with Impavido, and reduced her body temperature to 93 degrees, the same technique used to protect the brain from injuries that cause swelling. Several weeks after she was infected, doctors reported no presence of the amoeba in her spinal fluid.
The CDC recommends avoiding swimming in shallow, warm water, wear a nose clip, and avoid stirring up sediment while wading in shallow water.