How to avoid tapeworm infection
DEAR DOCTOR: I read a few years ago that someone wound up with tapeworms after eating raw fish, and now it has apparently happened again. What’s the deal?
DEAR READER: Let’s start by letting sensitive readers know that we’ll be discussing worms and intestines, with details that may be unsettling.
Six years ago, a Japanese man who frequently ate raw salmon became ill with stomach pains and watery diarrhea. According to an account published in the journal BMJ Case Reports, he discovered that a tape-shaped object had emerged from his anus. After infectious disease specialists examined the contents of the man’s stool, it was determined that the object, which was close to 40 inches long, was the Japanese broad or fish tapeworm.
Earlier this year, an emergency-room physician from California described a similar incident. A patient went to the hospital after he pulled a 5-footlong worm out of his body during an episode of bloody diarrhea. It turned out that the California man also ate raw salmon, every day.
Cases like this are rare, but the truth is that any time you eat raw or undercooked meat, you run the risk of ingesting
whatever parasites may have been present in the fish or animal. These range from minute, single-celled organisms that can only be seen with a microscope to the worms whose unnerving size help these stories of infection go viral.
Symptoms of infection include pain and diarrhea. Diagnosis is made by a microscopic examination of the patient’s stool for eggs, or for segments of the tapeworm itself. The good news is that a tapeworm infection can be successfully treated with several safe and effective drugs.
So how do you avoid tapeworm infection in the first place? The easiest and most effective way is to never eat raw or undercooked fish. The Centers for Disease Control and Prevention wants you to cook your fish to an internal temperature of at least 145 degrees. Freezing fish at minus 4 degrees or lower for seven days or at minus 31 or lower until solid also will kill any parasites.
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