Usually, the common parasite goes right through you. But the doctor said bad luck led the parasite into Rostro's bloodstream... and then into her brain.
Headaches are about one of the most common ailments that affect us all - but one Texas woman found out the source of the pain between her ears was anything but normal.
After months of consistent headaches, she went to the doctors to get some relief. Doctors then made a horrifying discovery.
They found sacs of larvae from eight tapeworm eggs inside her brain - and they were still growing.
Yadira Rostro, a 31-year-old mother from Texas, said: "Sometimes my sight was impaired... I could not see properly."
Neurosurgeon Richard Meyrat, who made the diagnosis, said: "They looked a little bit like eggs, and they have a clear sac. And inside it, a small tapeworm."
Parasite likely to have come from contaminated food
Dr. Meyrat said his patient likely picked up the parasite on a trip to Mexico two years ago after ingesting food contaminated with fecal matter, reports USA Today.
As the eggs grew, fluid slowly backed up in her brain, which caused the headaches. The images even shocked Dr. Meyrat, who had never seen anything like this before.
Rostro knows about the pictures, but has chosen not to see them. "I think she's just happy to be alive," Meyrat said. "Her headaches are gone, and she's feeling better."
And Rostro will make a full recovery after nearly nine months of pain. "I'm very grateful to God that I'm in his hands," she said.