Pork and ham are popular dishes for the holidays. But if they are not cooked properly, you could end up with hundreds of worms calling your digestive tract home.

A Chinese man named Zhu Zhongfa ate undercooked pork and unknowingly ingested the eggs of the dangerous parasite Taenia solium. As a result, his life was turned upside down as he started experiencing seizures and fainting episodes for weeks. This eventually lead him to seek medical treatment for his mysterious condition.

Only one month after he consumed the undercooked pork, doctors quickly identified the cause of Zhongfa’s seizures and fainting episodes. His body was utterly infected with tapeworms. These unwelcome guests had made themselves at home in his brain, lungs, and other parts of his body. The worm larvae had spread throughout his body via his bloodstream.