16-Year-Old Is 4th Known Person to Survive Brain Amoeba in 50 Years

Sebastian DeLeon was taken to Florida Children's Hospital in Orlando, Florida, with a severe headache on Aug. 7.
7:35 | 08/25/16

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Transcript for 16-Year-Old Is 4th Known Person to Survive Brain Amoeba in 50 Years
We start here tonight with what doctors are calling a medical miracle. Sit a by turns horrifying and moving story that involves a 16-year-old boy infected with a rare brain-eating parasite. His doctor told the parents to say their final good-byes. But then a desperate phone call and a frantic 30-minute drive in pajamas may have saved the day. It's the classic stuff of summer. Kids cooling off in water parks, Lakes, streams. But beneath the surface of these idyllic scenes there can be something genuinely terrifying. A common parasite that's been called a brain-eating amoeba. Infection is rare but 97% of people who get it die. He's currently walking, talking. It's a miracle. Reporter: 16-year-old Sebastian De Leon beat the incredibly bad odds and survived. We are so thankful that god has given us the miracle through this medical team and this hospital for having our son back. Reporter: A few days after swimming in a body of water on a private property in southern Florida, Sebastian was rushed to the hospital on August 7th with an excruciating headache, squeeze queasy, sensitivity to light. Doctors at Florida hospital for children at first thought his symptoms looked like meningitis but tests revealed something much worse, a parasite. The family immediately within four hours I had to tell them to say their good-byes. I had to tell them, tell him everything you want to tell your child, because I don't know from the time I put him to sleep to the time I take the tube out will he wake up. Reporter: Doctors made a crucial phone call to father-son team Todd and Michael Mclaughlin, who distribute a life-saving druggiveavido. I said, get in the car, go to the office, get the drug, bring it to the hospital right away. Reporter: Michael was less than 30 minutes away from the hospital. My mind went into one fear. Because I know how deadly the amoeba is. Then excitement. I think my adrenaline just went pumping from there. I'd already picked up the keys, was in my car. Reporter: He jumped into his car in pajamas, no time to waste, because the parasite eats away at the brain so quickly. By the time I dropped it off, it was just relief. I knew that this would definitely be one of the quickest times they'd received the drug. Reporter: Doctors administered the drug and then watched and waited as Sebastian lay in a medically induced coma for three days. We woke him up. And we decided to take the breathing tube out. And within hours he spoke. Reporter: The vast majority of people who get infected with this amoeba are not so fortunate. Ponds are host to a deadly amoeba that claimed the life of a local teenager last year. -- Whose daughter was dead the minute she jumped in the water, she just didn't know it. Looking into a deadly amoeba infection. Reporter: Out of the 138 known cases in the U.S. In the last 50 years or so, Sebastian is only the fourth survivor. The third, kalie hardic. Like Sebastian, kalie's troubles began with a seemingly low-risk summer outing to a water park. They had swings in the water you could swing on. They had like this jungle gym thing. These square blocks you can jump around on them. Reporter: A few days later kalie came down with headaches, vomiting, and a fever. All of a sudden the headache just started getting worse. Reporter: When her eyes rolled back into her head, kalie was rushed to Arkansas children's hospital. Doctors warned kalie's parents that she may only have a few days left. Without a proven treatment course, they tried something new. They induced a coma, they reduced her body temperature hoping to slow the parasite which thrives in high temperatures, and they gave her a cocktail of drugs including impavido, similar to what ended up saving Sebastian. A month later she was out of the coma with a long road ahead of her. With therapy she was able to relearn basic skills. She began to walk and talk, saying hello to her mom again. When I was able to first say that first word, I was so excited. I was just happy. Reporter: Dennis Kyle is a parasite researcher who's been studying this bug since the early '80s. He says the parasite enters through the nose, crosses the nasal lining into the sinuses, and finally invades the front brain where it starts eating away at the tissue. It could be from swimming, dunking your head, ingesting water into your nose. Reporter: However, there is a lot that scientists do not know. For example, why some people get sick and others don't. As if it's Numbers of amoeba, is it the person's immune system? There's nothing that really ties a string between getting infected and not getting infected. Reporter: One of the reasons why so many people do not survive this infection is because they are misdiagnosed and they simply run out of time. Which is what happened with 11-year-old Jordan snellski. He loved to make you laugh and smile. He had the most amazing smile. Reporter: His parents, Steve and Shelley, say their son contracted this deadly parasite while staying at a five-star resort in Costa Rica. By did horseback riding, zip lining. The next to last day, we swam in one of the pools at the resort. And the pool had water slides. And it was warm water. It was hot springwater. Reporter: The next day Jordan got a headache, then spiked a fever and started vomiting. He was diagnosed with meningitis and given antibiotics. He started having hallucinations. He didn't know who he was. He didn't know who we were. He didn't know where he was. Then he had a seizure. They brought in the icu team. They moved him downstairs. He never regained consciousness. They did some surgery. That's when they detected in a sample the amoeba. Reporter: Finally, the correct diagnosis. But it came too late. He died Wednesday morning at 6:30 A.M., six days and 12 hours after swimming. Today the snellskis are turning their own pain into awareness for other families. They've started a foundation in honor of their son with the hopes of educating other parents and doctors about the disease. Our fear is there may be more cases out there that are misdiagnosed or diagnosed as something else. The signs of this infection are the same as for meningitis. So headache, maybe confusion, stiff neck. Reporter: Medical experts agree parents should take children to the doctor if they see these strange symptoms, but they emphasize this deadly infection is exceedingly rare. Should we be thinking at all about prevention? I used to say, it's like getting struck by lightning. But getting struck by lightning is 10 times more common than getting this infection. So I shouldn't be worried about letting my kids swim in these bodies of water or swimming in one myself? You should worry. You should worry, do they know how to swim? You should worry about E. Coli which is common. Reporter: As for Sebastian, the 16-year-old in Florida, he's still in the hospital but doctors say he's making progress and his family is hoping for a full recovery. He's a very energetic,

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