Lorianne Surret's son fell dangerously ill from an infection that doctors say started with a mosquito bite.
"His lips were blue, his eyes were fixed," Surret said.
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Her 6-year-old son, Noah, suddenly started experiencing severe headaches. Then, he had a seizure.
"He screams out in pain from the headaches, and he's really just like a zombie," she said.
Doctors diagnosed Noah with La Crosse Encephalitis -- a rare condition passed through diseased mosquitoes, that can cause swelling in the brain.
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"It causes a fever and then a progressive headache and then it worsens from there," Dr. Sapna Parikh told ABC News.
While Noah's case is uncommon, the CDC says illnesses from mosquitoes, tick and flea bites tripled from 2004 to 2016. Experts say children are especially vulnerable.
"You want to watch -- is the headache worsening, is the fever persisting, if pain relievers aren't working or if the child is becoming more and more lethargic or like this family noticed, their child just didn't seem quite right," said Dr. Parikh. "That's when you want to worry."
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Noah is spending his days in a North Carolina ICU -- now on the road to recovery.
"In five days, I had not heard my child's voice. And that was the sweetest sound that I have ever heard," said Surret.
His mom hopes the story will sound the alarm for other parents.
"This is something that no parent should have to go through - just over a mosquito bite."