A man hospitalized with mysterious seizures was diagnosed with tapeworms that had been living in his brain for decades

• A man suffering from seizures, disorientation, and "speaking gibberish" had tapeworms in his brain.
• Doctors in the new case study said he had carried the parasites for years without symptoms.

Doctors who treated a man hospitalized with seizures, disorientation, and strange behavior said tapeworms had been living in his brain for years undetected, according to a case study published Thursday in The New England Journal of Medicine.

The 38-year-old man appeared to be in perfect health until one night when his wife awoke to find him on the floor, shaking and "speaking gibberish," according to the case report.

He was hospitalized, and doctors treated him for a seizure, noting that he was unresponsive to questions and seemed to be involuntarily gazing at the ceiling.

The man had no notable history of illness, no medication or drug use, and no symptoms until the seizures, his family told doctors.

The medical team at Massachusetts General Hospital eventually provided a diagnosis of cysticercosis, otherwise known as a tapeworm infection, which was confirmed via brain scans and blood testing.

Tapeworm infections can go undetected for years and can travel to the brain, causing seizures

Two decades earlier, the patient had emigrated from a rural area in Guatemala, where parasite-related illness is endemic, according to the case study.

Parasites from eating undercooked and unsanitary meat or fish can be passed from person to person if people with infections don't wash their hands after using the bathroom. Tiny parasite eggs in the person's poop can spread to other surfaces, or even food, and be ingested by someone else, passing the worms along.

Symptoms of infection include digestive upset, weight loss, and abdominal pain. But the parasite doesn't necessarily stay in your digestive system. The critters' larvae can also migrate throughout the body, into the muscle, and to the brain via the bloodstream, potentially causing a range of symptoms.

For instance, in a similar case of parasite-related seizures from 2019, a 43-year-old man in China complained of headaches, leading to the discovery of hundreds of tapeworms inside his brain. The symptoms, including seizures, started about a month after he dined on a pork hot pot he "felt unsure about."

In one 2020 case study, a woman complained of a sore throat, and doctors found an inch-long parasitic roundworm in her tonsil, most likely caused by sashimi she ate five days earlier.

It can also take years for symptoms to appear, however, since the parasites' eggs can lie in wait inside the body without prompting an immune response, Ars Technica reported.

Parasites can be dangerous, but infections are uncommon in the US

In regions where parasites are more common, including parts of Asia and Central America, as many as half of epilepsy cases are related to tapeworm infections in the brain, according to research. Tapeworms, specifically, can also be found in some parts of the US including Texas, Southern California, and New York City, according to the case study.

Most of us don't need to worry about walking around with parasites, Dr. Kyle Staller, a gastroenterologist at Massachusetts General Hospital (who was not involved with the case study), previously told Insider.

But fear of parasites has driven a trend toward viral "cleanses," products that claim to deworm the body to heal ailments as varied as brain fog and weight problems.

"The idea that there's a living organism inside us robbing us of nutrition and health is something people can latch onto, and fear is a selling point," Staller said.

The best way to prevent tapeworms is to cook meat, especially pork, to an internal temperature of at least 145 to 160 degrees Fahrenheit, according to the CDC. Thoroughly wash your hands and any plates or utensils after contact with raw meat. Always wash your hands after using the bathroom.