Hymenolepiasis B71.0

• Zestode, adults: 2-6 cm long and up to 1 mm wide. Hooks on the head for adhesion to the intestinal mucosa are present. The adults contain up to 200 proglottides.
• With the hooks the parasites attach themselves to the intestinal mucosa. The females release approx. 100-200 eggs/segment; the eggs are excreted with the stool and taken up by fleas or grain beetles. The cysticercoid develops in these.
• The beetles are ingested together with cereal meal by humans. In humans, the larvae are released; the scolex settles in the duodenum of the final host and begins to form proglottide chains (strobila). The preparation time (time until egg excretion) is about 7 days.
• In case of autoinfection by faecal-oral uptake of eggs, the preparation time is about 2-3 weeks. Endogenous autoinfection and infection from person to person are possible.

• Symptoms depend on the number of adult worms (up to several hundred are possible), milder infections are asymptomatic. Not infrequently, the disease triggers acute urticaria, which can become chronic if the disease is not recognised or treated.
• Typical symptoms: perianal and nasal itching, diarrhoea, abdominal pain (sometimes cramping), restlessness, sleep disorders.
• Less frequently: anorexia, vomiting, bloody diarrhoea, myalgia, headache, seizures.

Notice!

• Praziquantel (Biltricide; Cesol): Single dose 25 mg/kg bw p.o. (effective against adults and cysticercides).
• Alternatively: Niclosamide (Yomesan): 2 g/day p.o. for 7 days, if necessary repeat after 3 weeks (effective only against adults).

1. Dönges J (1988) Parasitology. With special consideration of human pathogenic forms". Thieme, Stuttgart
2. Mehlhorn H, Piekarski (2002) Ground plan of the parasitology, 6th edition. Spektrum Akademischer Verlag, Heidelberg