Something new to scare you. Federal scientists have identified an unsettling new cancer-like illness in a 41-year-old man, who is believed to have become infected through a common stomach bug.

The Washington Post reports that the case — the first known transmission of cancer cells from a parasite to a human — involves an HIV patient from Colombia who developed large tumors in various parts of his body, according to the Centers for Disease Control and Prevention.

Doctors biopsied the patient’s tumors and found they were like cancer cells had h ad strange qualities, and contacted the CDC for help.

Atis Muehlenbachs, a pathologist with the special branch of CDC that investigates mystery illnesses and deaths, told The Post this week that scientists first believed the case could involve a new type of infectious pathogen. But CDC tests revealed patient’s cells contained DNA snippets of a dwarf tapeworm, Hymenolepis nana.

"In the initial months, we wondered if this was a weird human cancer or some unusual, bizarre emerging protozoa-amoeba-like infection," he recalled. "Discovering these cells had tapeworm DNA was a big surprise — a really big surprise."

The CDC researchers, who published their findings in the New England Journal of Medicine, believe the Colombian man may have ingested some microscopic tapeworm eggs, after eating contaminated food.

Because of the man's compromised immune system, the tapeworms multiplied rapidly and the cells invaded other parts of his body.

"This is the first time we've seen parasite-derived cancer cells spreading within an individual," Muehlenbachs said. "This is a very unusual, very unique illness."