Tripartite dog tapeworm

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Tripartite dog tapeworm
Echinococcus granulosus

Echinococcus granulosus

Class : Tapeworms (Cestoda)
Subclass : True tapeworms (Eucestoda)
Order : Cyclophyllidea
Family : Taeniidae
Genre : Echinococcus
Type : Tripartite dog tapeworm
Scientific name
Echinococcus granulosus
( Batsch , 1786)

The tripartite dog tapeworm ( Echinococcus granulosus ; formerly Taenia echinococcus ), often referred to simply as "dog tapeworm," one of the most in dogs , wolves , foxes and other canids and in the roof and cats occur tapeworms . The carnivores , in whose small intestine it grows and lives, serve as final hosts . The intermediate hosts are mainly wild, herbivorous ruminants , but also domestic cattle, sheep, goats, pigs, horses, donkeys, as well as camels , rabbits , monkeys and humans . There are different strains of the dog tapeworm, each preferring different intermediate hosts.

There are two biotypes . The northern biotype has its development cycle between canids (wolves, domestic dogs) and wild ungulates ( elk , caribou / reindeer , white-tailed deer , roe deer ). It occurs mainly north of the 45th parallel. The southern biotype has its development cycle between domestic dogs and domesticated ungulates, especially sheep.

In Europe, the sheep tribe dominates and the parasite occurs mainly in countries where there is a lot of sheep farming. An infection of humans can (especially not through contact with secretions of infected final hosts entwurmter carried dogs) or in which by eating insufficiently heated offal, tapeworm Finns are.


E. granulosus is very small (3–6 mm), which often leads to massive infestation of the ultimate host, since no crowding effect can be observed. The head ( scolex ) of the worm has a protruding rostellum and a double row of hooks. A maximum of four (mostly three) tapeworm limbs ( proglottids ) are formed, of which the penultimate one is sexually mature. The last proglottid is about 2 mm long and contains several hundred eggs, which already contain mature larvae, so-called six-hooked oncospheres .


Life cycle and host change of Echinococcus granulosus

The dog tapeworm triggers cystic echinococcosis , a life-threatening disease both for animal intermediate hosts and for humans. The larval stages mainly settle in the liver, but also in the heart, lungs and other organs. In the case of dogs as main hosts ( final host ), in whose intestines the tapeworm grows, this disease, in contrast to the other tapeworm diseases in dogs , usually proceeds without clinical symptoms.

Autochthonous diseases are very rare in Central Europe; most cases of the disease are due to imports from endemic areas. There is a high prevalence in south-eastern Europe and Sardinia , but also in Turkey and the states of the Russian Federation . The three-membered ring dog tapeworm is also found in the British Isles . The secondary disease of the intermediate hosts, cystic echinococcosis, is endemic worldwide, also in Central Asia with the Tibetan highlands, in Africa , in Australia and in Central and South America , as well as in Canada and Alaska as well as in Arizona and New Mexico . In the United States of America , most infections have been diagnosed in immigrants from areas where Echinococcus granulosus is endemic. The risk factors include, above all, dogs without veterinary precautionary measures, uncontrolled slaughter in which dogs eat offal containing cysts , and unsanitary housing conditions. For hunting dogs at risk of infection if they are allowed the departure of killed ungulates to eat raw.

The dog tapeworm is one of the few representatives of the tapeworms in which the change of host is associated with a generation change ( metagenesis ). In the body of the intermediate host, there is a mass reproduction of these larval stages in a blister-shaped cyst ( hydatide ), in which the fins develop. This creates thousands of infectious heads . The cysts can be surgically removed, but they must not be injured in the process, as a rupture causes the larvae to “sow”, which then develop elsewhere. In addition, the contents of the cyst in the body can trigger an anaphylactic reaction after a cyst burst .

Reporting requirement

In Germany, the direct or indirect detection of Echinococcus sp. (i.e. also of the tripartite dog tapeworm) not subject to notification by name according to Section 7 (3) of the Infection Protection Act (IfSG). The reporting obligation primarily concerns laboratories (see § 8 IfSG).

In Austria, suspected cases of illness and death from dog tapeworms (Echinococcus granulosus) are notifiable (in accordance with Section 1 (1) (1) of the 1950 Epidemic Act). Doctors and laboratories, among others, are obliged to report this ( Section 3 Epidemics Act).


  • Volker Storch, Ulrich Welsch: Kükenthal's guidelines for the zoological internship. 24th revised edition. Spektrum Akademischer Verlag, Heidelberg et al. 2002, ISBN 3-8274-1111-4 .

Individual evidence

  1. Hirvelä-Koski, Haukisalmi, Kilpelä, Nylund, Koski: Echinococcus granulosus in Finland
  2. OREGON DEPARTMENT OF FISH AND WILDLIFE: Parasitic Tapeworm (Echinococcus granulosus)
  3. a b Barbara Hinney and Anja Joachim: Gastrointestinal parasites in dogs and cats. In: Kleintierpraxis 58 (2013), pp. 256–278.
  4. Centers for Disease Control and Prevention: Cystic Echinococcosis
  5. Overview of alveolar and cystic echinococcosis in Germany
  6. Oyeduntan Adejoju Adediran, Temitope Ubaidat Kolapo, Emmanuel Chibuike Uwalaka: Echinococcus granulosus Prevalence in Dogs in Southwest Nigeria Journal of Parasitology Research 2014
  7. ^ Bangor Veterinary Hospital: Hunting, Tapeworms and your Dog