Editor's note: This popular story from the Daily Briefing's archives was republished on June 16, 2020.

Gerardo Moctezuma had been experiencing violent headaches and drowsiness for months, but it wasn't until he fainted at a soccer game that he sought medical help, leading providers to discover a tapeworm in his brain, Timothy Bella reports for the Washington Post.

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A 'rare and truly extraordinary' case

For several months, Moctezuma experienced headaches that were so intense he would vomit, and his drowsiness had been gradually intensifying, Bella reports. But he didn't seek medical help until May 2019, when he fainted at the soccer game. Moctezuma was taken to Dell Seton Medical Center, where Jordan Amadio, attending neurosurgeon at the Ascension Seton Brain and Spine Institute, noticed something strange in an MRI of Moctezuma's head: Moctezuma had a life-threatening tape worm about an inch and a half long, living near his brain stem.

He was immediately rushed into emergency surgery. During the difficult, three-hour procedure Amadio had to navigate an area of the brain full of essential nerves and blood vessels. But he discovered that the tapeworm had been living in a single cyst next to Moctezuma's brain stem, as opposed to being dispersed in numerous larva.

According to Amadio, Moctezuma's symptoms had gotten worse because of neurocysticercosis, which occurred because of the tapeworm. The cyst caused hydrocephalus, a condition that increased pressure in Moctezuma's skull and threatened his life.

Moctezuma's case has been described as "'rare and truly extraordinary,'" Bella reports.

"It's a remarkable case where a patient came in and, if he had not been treated urgently, he would have died from tremendous pressure in the brain," Amadio said.

Where did the tapeworm come from?

According to Bella, it's not entirely clear how the tapeworm got into Moctezuma's brain, but Moctezuma believes it could have come from eating undercooked pork while he lived in Mexico 14 years ago. "Given that pigs often act as intermediary hosts for tapeworms, consuming undercooked pork is perhaps the most common way to transmit a parasite," Bella reports.

But Amadio believes poor hygiene was the culprit. Bella writes that while living in Mexico someone around Moctezuma might have eaten undercooked pork and passed a microscopic egg from the tapeworm to Moctezuma "in a case of fecal-oral contamination, which is a typical form of infection," Bella notes.

Either way, Amadio said, "It's certainly possible that [Moctezuma] was infected while living in Mexico and the tapeworm was incubating in his system for many years."

Amadio added that, while Moctezuma's particular case was rare, CDC tracks about 1,000 cases of neurocysticercosis in the United States each year.

"This was an unusual case because it required an emergency surgery," Amadio said. "Thankfully, once the lesion was removed, the patient had a spectacular outcome and is happy and living with his family and back to work" (Bella, Washington Post, 1/31).