Brain Worms Aren’t Super Common. How Did RFK Jr. Get One?

Robert F. Kennedy Jr. is opening up about a pretty scary health journey. The 70-year-old presidential candidate told The New York Times in a recent interview that he had a parasite in his brain. According to Kennedy, he was initially struggling with severe memory loss and mental fogginess in 2010 that was so intense, a friend worried that he might have a brain tumor. Imaging scans revealed a dark spot on his brain, which he was told by several doctors was a tumor and advised to schedule brain surgery.

Kennedy was packing for a trip to have the procedure done when another doctor called and told him he thought the politician had a dead worm in his brain. The worm had apparently gotten into Kennedy's brain, eaten a portion of it, and then died, Kennedy explained in a 2012 deposition reviewed by the Times. After having several more tests done, doctors concluded that the cyst they saw on the scans was actually the calcified remains of a parasite.

The information about RFK Jr.'s brain worm has raised a lot of questions about how you can get a brain parasite in the first place and what happens next. We spoke to several doctors to break it down.

It's not entirely clear how RFK Jr. ended up with a parasite in his brain. According to the Times, he suspects he contracted the parasite during a trip through South Asia, but isn't entirely sure.

"One of the most common means that you can potentially get parasitic infections of the central nervous system is if you eat undercooked or raw vegetables that may have been contaminated with parasitic eggs or various developmental forms," says Thomas Russo, MD, professor and chief of infectious disease at the University at Buffalo in New York. Another way you can get a brain worm, per Russo: If you happen to touch an object, food, or surface that is contaminated with parasitic eggs and then touch your mouth. "You could end up ingesting them," he tells PS.

Kennedy said that around the same time he was diagnosed with a brain parasite, he was also diagnosed with mercury poisoning, which was likely caused by eating too much fish.

"I have cognitive problems, clearly," he said in the deposition, per the Times. "I have short-term memory loss, and I have longer-term memory loss that affects me."

It's not clear if the parasite itself led to the memory loss or if it was due to mercury poisoning, which is a condition that's linked to memory loss and mental disturbances. It's possible to experience memory loss with a parasite in your brain, says Walavan Sivakumar, MD, board certified neurosurgeon and director of neurosurgery at Pacific Neuroscience Institute-South Bay in Torrance, CA — it's just not likely to be the most common symptom you'd experience. Dr. Russo agrees. "Symptoms can be myriad, but headaches are the most common," he tells PS.

Doctors stress that it's not common to have a parasitic infection of the brain in the US. "It is more common in other parts of the world, though," Dr. Russo says. However, Dr. Sivakumar says he's seen "quite a few cases" of brain parasites in patients. There isn't a lot of data on how common these infections (also known as neurocysticercosis) actually are in the US. However, the journal Emerging Infectious Diseases notes that there are around 2,000 hospitalizations a year in the country due to neurocysticercosis. "It's not common, but it happens more than you'd think," Dr. Sivakumar tells PS.

The signs and symptoms of having a brain parasite can vary, depending on where it is and what it does, Dr. Sivakumar says. Still, here are few side effects to look out for:

Doctors stress that the odds of having a brain worm when you live in the US are very low. "A parasitic infection would cause far less than 0.1 percent of cases of all headaches," Dr. Sivakumar says. Still, he says there are a few signs of a parasitic brain infection that you'd want to get checked out.

"If you're having unrelenting headaches and they're not getting better with standard medications, or you don't have a history of headaches and you have something you can't explain that won't go away, it's worth going to your primary care doctor," he says.

Having headaches and other symptoms of a parasitic infection could also be an indication of a stroke or brain hemorrhage, which are medical emergencies, Dr. Russo points out. If you develop sudden weakness in your arms and legs, vision loss, and hearing loss, along with your headache, he recommends seeking medical care right away. "It's highly unlikely to be a parasite, but critically important to seek care," Dr. Russo says. "In those situations, time is of the essence."

If doctors determine that you do, in fact, have a brain worm, they may or may not recommend treatment. Anti-parasitic drugs may help if the parasite is still alive, Dr. Sivakumar says. And if there is a blockage of the flow of spinal fluid, brain surgery may be needed. Other times, doctors may opt to let the parasite run its course. "If they're not causing significant symptoms, sometimes treatment isn't even needed," Dr. Russo says. Parasites can die in the brain, he points out, as in Kennedy's case. The presidential candidate says he no longer struggles with memory loss and fogginess, and has no lingering symptoms of the parasite, which he says didn't require treatment.

Ultimately, don't let Kennedy's experience psych you out. "Everybody gets headaches occasionally," Dr. Sivakumar says — and yours is probably nothing. That said, if you're experiencing persistent and reoccurring headaches that just won't quit, contact a healthcare provider to figure out exactly what's going on.

Korin Miller is a writer specializing in general wellness, health, and lifestyle trends. Her work has appeared in Women's Health, Self, Health, Forbes, and more.