(CNN) - An experimental drug could be the key to saving a 12-year-old girl. Kali Hardig is battling for her life after coming into contact with a brain-eating parasite during a trip to an Arkansas water park.
When Hardig arrived at Arkansas Children's Hospital, she was so exhausted she could not answer the doctor's question.
The doctor ran test that show the child had a rare and almost always deadly infection, a brain-eating amoeba, swimming around in her spinal fluid.
To preserve brain tissue, doctors induced a coma and cooled Hardig's body to 93 degrees. Doctors also turned to the Centers for Disease Control (CDC) for an experimental anti-amoeba drug, unsure if it would work.
Apparently it has. Now there is now trace of the amoebas in Hardig's spinal fluid.
"Day by day she's showing slow improvement and we're all very optimistic," Dr. Sanjiv Pasala, pediatrician at Arkansas Children's Hospital, said. "Killing the amoebas is one thing, but managing brain swelling and the aftermath of the infection and the irritation to the brain is really the critical part in having a patient survive."
If Hardig pulls through, she will beat the odds. Only one person in the U.S has survived this disease in the past 50 years.