RFK Jr. Says Doctors Found a Dead Worm in His Brain

Dr. Clinton White, a professor of infectious diseases at the University of Texas Medical Branch in Galveston, said microscopic tapeworm eggs are sticky and easily transferred from one person to another. Once hatched, the larvae can travel in the bloodstream, he said, “and end up in all kinds of tissues.”

Though it is impossible to know, he added that it is unlikely that a parasite would eat a part of the brain, as Mr. Kennedy described. Rather, Dr. White said, it survives on nutrients from the body. Unlike tapeworm larvae in the intestines, those in the brain remain relatively small, about a third of an inch.

Some tapeworm larvae can live in a human brain for years without causing problems. Others can wreak havoc, often when they start to die, which causes inflammation. The most common symptoms are seizures, headaches and dizziness.

There are roughly 2,000 hospitalizations for the condition, known as neurocysticercosis, each year in the United States, according to the journal Emerging Infectious Diseases.

Scott Gardner, curator of the Manter Laboratory for Parasitology at the University of Nebraska-Lincoln, said that once any worm is in a brain, cells calcify around it. “And you’re going to basically have almost like a tumor that’s there forever. It’s not going to go anywhere.”