Karla Bennett
May 2012

• It is known as the “fish tapeworm”
• Diphyllobothrium latum is a cestode (a hermaphrodiditic worm that is a parasite of the vertebrate intestinal tract).

• Plerocercoid-the larval form. Also the infective stage found in the raw flesh of freshwater fishes.
• D. latum- the adult worm
• Proglottids- the segments of the flat worm. Each contains both male and female reproductive organs
• Scolex- the part on the anterior end that is long and spoon-shaped. It is what the worm uses to attach itself to the intestinal tract.

• Its distribution is worldwide
• It occurs where pickled or insufficiently cooked fish are part of the cultural diet. (Northern temperate areas)

• Intermediates: Freshwater fish and copepods
• Definitive host: Humans and other vertebrates.

• constipation
• diarrhea
• fatigue
• obstruction of the bowel
• pernicious anemia (caused by vitamin B12 deficiency) which can lead to subacute combined degeneration of spinal cord
• stomach pain
• vomiting
• weight loss.

• Examination of a fecal sample for eggs and proglottoids is the quickest way to diagnose
Diphyllobothriasis.
• All diphyllobothrium species respond to the same treatment.
• The best method is a diatrizoic acid injection into the duodenal wall.
• Praziquantel or niclosamide are not as effective because they do not remove the attached head from the intestine wall.

• Cook fish properly. If you eat sashimi or sushi, freeze it first at -10 °C (or below) for two days to kill the tapeworm larvae.
• Do not defecate in water. If the fish tapeworm larvae cannot get in touch with the intermediate hosts, they cannot infect humans.

• http://www.parasitesinhumans.org/diphyllobothriumlatum-fish-tapeworm.html
• http://www.stanford.edu/group/parasites/ParaSites200
5/Diphyllobothriasis/New%20Folder/index.htm
• http://www.dpd.cdc.gov/dpdx/html/Frames/A-
F/Diphyllobothriasis/body_Diphyllobothriasis_mic1.ht
m
• http://www.human-healths.com/wpcontent/uploads/2011/08/Diphyllobothrium2.gif
• http://www.kmle.co.kr/search.php?Search=latum
• http://www.ifood.tv/network/pickled_herring
• http://www.realmonstrosities.com/2011/02/copepod.ht
ml

• Name 3 symptoms of Diphyllobothriasis.
• What is the name of the best drug for treatment and why is it better than the others?
• Name the two intermediate hosts in the lifecycle.
• What is the name of the anatomical body part of the parasite that it uses to attach itself to the intestine?
• Why does the entire adult worm need to be removed?