Sushi’s to Blame for a Man’s 5-Foot Tapeworm

By Carl Engelking | January 22, 2018 1:20 pm

(Credit: Shutterstock)

A Fresno, Calif. man is rethinking his diet after one of his favorite dishes came back to bite him in the butt.

Dr. Kenny Banh who works in the emergency room in the Community Regional Medical Center in Fresno shared a horrifyingly fascinating story about one of his patients on a recent episode of “This Won’t Hurt a Bit,” a podcast where experts of medicine share strange and fascinating medical stories.

As Banh explained, a young man came into the emergency department complaining of bloody diarrhea. He also specifically asked to be treated for a tapeworm. Banh said he’s seen patients who think they have a tapeworm, but their fears are often unwarranted. But this time, Banh’s patient had proof.

“I see next to him he’s got this little grocery bag, plastic bag, sitting next to him. I said, ‘I hope it’s not a stool sample.” He goes, ‘No. It’s the worm,” Banh explained on the show.

Banh peeked inside the bag. Sure enough, there was a tapeworm wrapped around a cardboard toilet paper tube.

The patient, Banh said, had been quite worried. After using the bathroom, he noticed blood in his stool. He also noticed something else hanging out of his rear. The man, fearing this strange new appendage was actually a piece of his intestines, gave it a tug. And he kept tugging.


Yup, that’s it. (Credit: Kenny Banh)

When he picked it up to examine what had just exited his body, it moved.

The patient, relived his entrails weren’t falling out, coiled the worm onto a cardboard tube and went to the hospital. Banh said the worm, known generally as a helminth, stretched to a length of 5 feet, 6 inches. How the tapeworm entered the patient’s body stumped Banh, until the patient revealed he absolutely loves eating salmon sashimi, a raw fish dish that’s a Japanese delicacy.

Several salmon species are the principle sources of Diphyllobothrium nihokkaiense, or the Japanese broad tapeworm. It was previously thought that this parasite was a problem unique to Asia, but in 2017 the Centers for Disease Control warned that North American fisheries were also at risk. They published a study that showed wild salmon harvested in Alaska were also plagued by the parasite.

“Our main intent is to alert parasitologists and medical doctors about the potential danger of human infection with this long tapeworm resulting from consumption of infected salmon imported (on ice) from the Pacific coast of North America and elsewhere,” the CDC researchers wrote.

Salmon are typically caught and shipped on ice, rather than frozen. Therefore, tapeworm larvae can survive their trip from the ocean to your sushi plate. Cooking salmon or freezing it is enough to kill the parasite.

While the thought of a 6-foot tapeworm calling your insides home is haunting, tapeworms typically aren’t a major threat to your health. Oftentimes, they can dwell inside the intestine for years undetected. In rare cases, a tapeworm might cause gall bladder disease, obstruct sections of the intestine or cause a vitamin B12 deficiency.

Treating a tapeworm is very simple. A patient takes one dose of a de-worming medication, and that’s usually enough to kill them all.

Banh confirmed that the patient will probably avoid sashimi for now.

CATEGORIZED UNDER: Health & Medicine, top posts
  • Uncle Al

    Raw fish contains thiaminase, as do many “holistic” foods.


    Chronic thiamine deficiency engages irreversible peripheral neuropathies typical of alcoholics and consonant with diabetics. Physical reality is not a peer vote.

    • kapnlogos

      Is it Uncle Artificial Intelligence?

      • Uncle Al

        1957, Sputnik, US Congress imagines H-bombs dropping from orbit. 1958, National Defense Education Act. Uncle Al and so any others are product. 1965, President Johnson’s “Great Society” permanently cripples US education.

        I repudiate a Democrat Party aristocracy of donated equality of achievement for others. Support evolution – shoot back.

        • kapnlogos

          Is that a yes? It seems your algorithm has a little problem staying on topic.


      Interesting, but [from your link]:
      Thiaminases are present in the viscera of certain raw fishes and shellfishes, especially carp. Humans, even sushi lovers, rarely eat enough raw fish in their diet to constitute a problem. “

  • gr8bkset

    If the worm is relatively safe, it can be marketed in the developed world as a non-surgical weight loss alternative to gastric bypass. There are already billions of microbes in our intestines, so what’s another tapeworm? You can the process with a pill – also noninvasive (sort of…).

  • John Thompson

    So then just cook your food. It’s not 100,000 years ago anymore, we cook food for good reasons.
    Oh, and alot of sushi isn’t raw or even fresh – it’s frozen.
    That’s right – the fancy delicacy is often just frozen fish.
    Of course the reason is not just practicality of transporting the fish from the catch to the table – freezing helps kill parasites in certain fish species.
    Oh, and cooking makes most food taste better.


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