Diphyllobothrium Latum Ian Moreau

Morphology & Physiology Diphyllobothrium latum is in the class Cestoda and in the order Pseudophyllidia The scolex is very small, only about 1mm wide and 9~20mm long, with bothria on either side Gravid proglottids are wider than they are long and can be as wide as 2cm The Adult worm can reach up to 15m and 4000 proglottids long

Morphology & Physiology (cont) Rosetta shaped ovary The proglottids change genders as they grow, first male, then female Although the worm can inseminate itself, it often mates with other worms in its habitat (i.e. your gut) which makes it a reciprocally inseminating hermaphrodite D. nihonkaiense

Life Cycle D. latum follows the standard pseudophyllidia life cycle Primary intermediate host is a copepod, the secondary is a freshwater fish, usually trout, salmon, perch or pike Definitive host is usually a human or bear

Pathology Causes diphyllobothriasis, also known as Jewish (or Scandinavian) housewife’s disease Most infestations are asymptomatic, but you might feel: abdominal discomfort, abdominal cramps, intestinal obstruction, abdominal distension, diarrhea, vomiting, or weight loss. Another affect is loss of vitamin B-12, which can lead to pernicious anemia like symptoms

Diagnosis Proglottids observed in stool Eggs in stool Numerous enough, no concentration needed

Prevention and Treatments Prevention- thoroughly cook all fish or don’t eat fish Treatments Praziquantel-evidence that it increases permeability of schistisome membrane to calcium ions Niclosamide-lethal on contact with tapeworm cells

References Diphyllobothriasis. CDC DPDx. 13 Dec. 2002 <http://www.dpd.cdc.gov/DPDx/HTML/Diphyllobothriasis.asp?body=Frames/A-F/Diphyllobothriasis/body_Diphyllobothriasis_page1.htm> Five Cases of Diphyllobothrium nihonkaiense Infection with Discovery of Plerocercoids from an Infective Source, Oncorhynchus masou Ishikawae. by Katsuhiko Ando; Ken Ishikura; Tetsuya Nakakugi; Yoshiki Shimono; Takuya Tamai; Masahiro Sugawa; Wutipong Limviroj; Yasuo Chinzei. The Journal of Parasitology © 2001 The American Society of Parasitologists Diphyllobothrium Latum Infection. www.emedicine.com. 6 June 2006. <http://www.emedicine.com/ped/topic597.htm> Diphyllobothrium latum. Web Atlas of Medical Parisitology. 2003. <http://www.atlas.or.kr/atlas/alphabet_view.php?my_codeName=Diphyllobothrium%20latum> Diphyllobothrium spp.. U.S. FDA Bad Bug Book. 14 June 2006. <http://www.cfsan.fda.gov/~mow/chap26.html>