After COVID infection, 3-year-old suffers rare and severe brain swelling

A 3-year-old boy is facing a long recovery after contracting COVID-19 on a family vacation. Now, a Sylmar family hopes his story will help others.

Doctors say it's a stark reminder why COVID vaccinations and the booster shot are so important.

Before CJ Mercado tested positive for COVID-19, he was smiling and dancing like any other child his age. But, within a few days, he was in the hospital clinging to life.

"Doctors ended up coming in and they said that... he had increased pressure in his brain... so just prepare yourself," said Melissa Mercado, CJ's mom.

Around mid July, during CJ's third birthday, he was on his first family trip since the stay-at-home orders prompted by the pandemic.

On the way home, CJ came down with a high fever and headaches. His parents took him to Providence Cedars-Sinai Tarzana Medical Center.

"At that point he was unresponsive and having seizures," Mercado said.

CT scans revealed CJ's brain was swollen. Doctors diagnosed him with Acute Demyelinating Encephalomyelitis. Inflammation destroyed the protective sheath surrounding his nerve cells.

"The signal that is sent from one nervous system to another was disrupted," said Dr. Ira Wardono.

She said within 12 hours, CJ could not walk or talk. He was transferred to UCLA, where he stayed in the ICU for 20 days.

"They just kept telling us that, with something like this, it was gonna take time," said David Mercado, CJ's dad.

He pulled through, but CJ's road to recovery will take a very long time.

"Rehab can take anywhere from one to five years," said Wardono.

Now four months later, CJ's personality is back.

Doctors can't say with certainty that COVID is the culprit, but CJ's parents wish they didn't wait to vaccinate him.

"We were gonna come back from our trip and he was going to get it... It could have been a lot different for him," Mercado said.

Any viral or bacterial infection can cause this type of brain inflammation, although it's extremely rare. The advice remains the same. Stay away from sick people and get vaccinations as soon as they become available.

"It's serious. It can alter your life," Mercado said.