"He's done tremendously well. He's walking, he's speaking, he went outside for the first time to get some fresh air -- he's ready to go home," Dr. Humberto Antonio Liriano, a critical care physician, told reporters.
It's remarkable because he is only the fourth person in the United States to survive an infection from this parasite, called Naegleria fowleri.
On vacation with his family in Orlando, DeLeon had a severe headache while they were at a theme park on August 7. The pain became so bad, Liriano explained, the teen "couldn't tolerate people touching him."
A search for local hospitals ensued and they fortuitously discovered Florida Hospital for Children, where they brought the teen. Later, they learned doctors there were uniquely knowledgeable about this amoeba -- they'd attended special seminars on the topic earlier this year.
When DeLeon arrived at the hospital, Dr. Dennis Hernandez, the ER doctor working at the time, immediately identified symptoms of meningitis and took a sample of the teen's cerebral spinal fluid. The samples were positive for the brain-eating amoeba.
Explaining the amoeba
Three other people are known to have been infected with primary amebic meningoencephalitis, the infection caused by the amoeba, this year. DeLeon is the only one who has survived.
The brain-eating amoeba cannot infect you if you drink contaminated water, explained Dr. Rajan Wadhawan, chief medical officer at Florida Hospital for Children. The parasite becomes a danger "only when it goes up the nose forcibly," Wadhawan said. Most patients survive only 12 to 13 days.
The Florida Department of Health said DeLeon was infected earlier this month while swimming on private property in Broward County.
Hearing DeLeon's test results, the entire hospital worked together, Liriano recounted. Calls were placed to Profounda Inc., the Orlando-based drug company that makes an anti-parasitic called miltefosine (sold as Impavido), that was FDA approved in March for another use. Within 12 minutes, the drug was delivered to the hospital.
Liriano and a team of pediatric infectious disease doctors, with assistance from the US Centers for Disease Control and Prevention, worked together with one goal in mind: to save his life. They placed the teen on a breathing tube and in a drug-induced coma. They administered miltesfosine and other antimicrobials and ran tests daily to check for the amoeba in hopes of getting a negative result.
That came 72 hours after treatment began, indicating the amoeba was gone. "We decided to take the breathing tube out and within hours, he spoke," said Liriano, who began to cry as he decribed his patient's recovery. He said he has been doing "tremendously well."
DeLeon will need rehab, but is ready to return home to South Florida with his family.
Brunilda Gonzalez, DeLeon's mother, expressed her appreciation at the news conference. "First to God and all his power for everything he has done in saving our kid's life," she said. "We are so thankful for this gift of life... God has given us a miracle through this hospital staff."
Gonzalez acknowledged how hard the staff worked to get the medication to her son just in time to save his life, and also noted that her son's experience might be helpful to others.
Beating the odds
According to the CDC, between 1962 and 2015, there were 138 known cases of primary amebic meningoencephalitis.
In 2013, then 12-year-old Kali Hardig was infected with the parasite while swimming at a water park. After nearly seven weeks in the hospital, the Arkansas pre-teen was able to return home. Hardig recovered and went back to school that fall.
The same summer, an 8-year-old boy in Texas also survived, although he suffered brain damage. According to the CDC
, that outcome was believed to be due to a delay of "several days after his symptoms began" before treatment started.
The only other known survivor in the United States, who was not treated with miltefosine, was a patient in California in 1978.
Having worked with amoeba cases in the past, Liriano appeared to savor the rare outcome for his patient.
"This is a story we need to tell about Sebastian DeLeon," Liriano said.