Twelve-year-old Zachary Reyna from Florida was infected by a rare brain-eating amoeba he contracted from kneeboarding at a water-filled ditch by their house.

Zachary now remains sedated at Miami Children's Hospital as family members and friends keep vigil on his bedside, the Associated Press reported.

"[It] will actually eat away at the tissue; it literally eats the tissues. It is a severe form of meningitis where your brain will be eaten by the amoeba,'' attending physician to Zachary, Dr Mark Heulitt, told KATV.

Zachary's older brother, Brandon, holds on to the hopes that his brother will recover and they will be playing baseball in no time at all.

"He's fighting and he's strong, he's really, really strong,'' Brandon said.

Zachary's parents were alarmed when he slept the whole day. They initially suspected that Zachary had just contracted a 24-hour virus, but their instincts told them that something was terribly wrong with their supposedly hyperactive son.

According to the Centre for Disease Control and Prevention, the brain-eating amoeba is extremely rare that there were only 32 reported cases from 2001 to 2010. Most of the cases happened in the Southeast.

If Zachary will recover from the rare brain-eating amoeba, he will only be the fourth to have survived the rare brain parasite.

According to a report from CNN, a 12-year-old girl from Arkansas, Kali Hardig, was able to survive the same rare brain eating amoeba that infected her a couple of weeks ago.

According to a spokesman from the Arkansas Children's Hospital, Kali is now undergoing rehabilitation and is showing remarkable progress.

Rare brain-eating amoeba infections were nearly fatal but Zachary's parents were given hope by Kali's survival.

The rare parasite is scientifically called Naegleria fowleri and usually found in warm, fresh water, CDC said. The amoeba can enter the nose and travels to the brain.

"This infection is one of the most severe infections that we know of. Ninety-nine percent of people who get it die," according to Dr. Dirk Haselow of the Arkansas Department of health.

The primary symptoms that a person was infected by the parasite are headache, fever, nausea, vomiting and a stiff neck.

"Later symptoms include confusion, lack of attention to people and surroundings, loss of balance, seizures and hallucinations. After the start of symptoms, the disease progresses rapidly and usually causes death within one to 12 days, as stated from CDC's Web site."

To avoid the risk of contracting the rare brain-eating amoeba, CDC provides the following tips:

  • Avoid swimming in fresh water when the water temperature is high and the water level is low.
  • Hold your nose shut or use nose clips.
  • Avoid stirring up the sediment while wading in shallow, warm freshwater areas.
  • If you are irrigating, flushing or rinsing your sinuses (for example, by using a neti pot), use water that has been distilled or sterilized.