A 52-year-old Florida man presented to hospital with complaints that his usual migraines had worsened over the past four months.

On closer inspection using a CT scan, the doctors discovered his severe headaches were the result of several cysts throughout his brain.

Infectious disease experts undertook blood tests to confirm these were larval cysts of the pork tapeworm (Taenia solium), and that the man's headaches were symptoms of neurocysticercosis.

A team of US physicians and researchers explain in a case report of the incident that the source of the patient's infection is puzzling. The man said he had not traveled to any countries or farms which increased the risk of exposure to infected pork, or to food or water contaminated with infected feces.

Neurocysticercosis is very rare outside of classic exposures or travel to countries with poorer sanitation, and before now, was thought to be nonexistent in the US.

The man did admit to a fondness for lightly-cooked, floppy bacon, having eaten it for most of his life. That could have accounted for him ending up with a tapeworm inside him, also known as taeniasis, but it doesn't explain how the cysts got into his brain.

"It can only be speculated, but given our patient's predilection for undercooked pork and benign exposure history, we favor that his cysticercosis was transmitted via autoinfection after improper handwashing after he had contracted taeniasis himself from his eating habits," the authors write.

"Taeniasis occurs when consuming undercooked pork and the larval cysts embedded within, while cysticercosis is contracted when humans ingest eggs found in the feces of other humans with taeniasis."

The doctors suggest the man probably had a tapeworm from eating undercooked bacon, and then swallowed some of its eggs from his own poop.

Let this be a good reminder to wash your hands, people.

Neurocysticercosis poses risks far beyond migraines, with up to 80 percent of cases experiencing seizures. Depending on which parts of your brain the cysts are embedded in, symptoms can range from nonexistent to profound, with classic signs including focal neurological deficits like partial paralysis, weakness, numbness, and losing control over movement; increased pressure in the skull; and signs of cognitive decline, like confusion and memory loss.

The case study authors say that while migraine on its own doesn't warrant neuroimaging, "acute and persistent changes in migraine frequency or character should raise concern for a new pathology, as in our patient."

This man was treated with anti-parasitic and anti-inflammatory medicines, after which his brain worms – and the headaches they were giving him – cleared out.

The authors are concerned that the man may have gotten sick from US pork.

"It is historically very unusual to encounter infected pork in the United States, and our case may have public health implications," they write.

This case has been published in the American Journal of Case Reports.