Skip to main content
    • Aa
    • Aa

Influence of environmental factors on the infectivity of Echinococcus multilocularis eggs

  • P. Veit (a1), B. Bilger (a1), V. Schad (a1), J. Schäfer (a1), W. Frank (a1) and R. Lucius (a1)...

The sensitivity of eggs of Echinococcus multilocularis to environmental and controlled laboratory conditions was tested. Egg material was exposed and the infectivity was subsequently monitored by in vitro activation and by oral infection of the natural host, Microtus arvalis. To study the impact of environmental conditions in an endemic area of south-western Germany, eggs were sealed into bags of nylon mesh and exposed to the natural climate during various seasons. The maximal survival time of eggs was 240 days in an experiment performed in autumn and winter and 78 days in summer. A study of the tenacity of eggs under laboratory conditions revealed a high sensitivity to elevated temperatures and to desiccation. At 45 °C and 85–95% relative humidity the infectivity was lost after 3 h as well as after 4 h exposure to 43 °C suspended in water. Exposure to 27% relative humidity at 25 °C as well as exposure to 15% relative humidity at 43 °C resulted in a total loss of infectivity within 48 and 2 h, respectively. Temperatures of 4 °C and of –18 °C were well tolerated (478 days and 240 days survival, respectively), whereas exposure to –83 °C and to –196 °C quickly killed off the eggs (within 48 h and 20 h, respectively). Eggs of E. multilocularis were not killed off by exposure to various commercially available disinfectants applied according to the manufacturers' instructions and by exposure for 24 h to low concentrations of ethanol. Irradiation with 40 krad. from a 137Caesium source prevented the development of metacestodes but allowed seroconversion of infected rodents.

Linked references
Hide All

This list contains references from the content that can be linked to their source. For a full set of references and notes please see the PDF or HTML where available.

C. W. Colli & J. F. Williams (1972). Influence of temperature on the infectivity of eggs of Echinococcus granulosus in laboratory rodents. Journal of Parasitology 58, 422–6.

M. A. Gemmell (1969). Immunological responses of the mammalian host against tapeworm infections. X. Immunization of sheep against Taenia hydatigena and T. ovis with chemically or physically treated embryos. Experimental Parasitology 26, 5866.

R. Gönnert & H. Thomas (1969). Einfluβ Von Verdauungssäften auf die Eihüllen von Taenia-Eiern. Zeitschrift für Parasitenkunde 32, 237–53.

G. F. Laws (1967). Chemical ovacidal measures as applied to Taenia hydatigena, Taenia ovis, Taenia pisiforntis, and Echinococcus granulosus. Experimental Parasitology 20, 2737.

G. F. Laws (1968). Physical factors influencing survival of taeniid eggs. Experimental Parasitology 22, 227–39.

J. R. Lawson & M. A. Gemmell (1983). Hydatidosis and cysticercosis: the dynamics of transmission. Advances in Parasitology 22, 261308.

A. Mackie & I. W. Parnell (1967). Some observations on taeniid ovicides: The effects of some organic compounds and pesticides on activity and hatching. Journal of Helminthology 41, 167210.

A. F. Petavy , S. Deblock & S. Walbaum (1991). Life cycles of Echinococcus multilocularis in relation to human infection. Journal of Parasitology 77, 133–7.

E. L. Schiller (1955). Studies on the helminth fauna of Alaska. XXVI. Some observations on the cold-resistance of eggs of Echinococcus sibiricensis Rausch and Schiller, 1954. Journal of Parasitology 41, 578–82.

P. H. Silverman (1954). Studies on the biology of some tapeworms of the genus Taenia. I. Factors affecting hatching and activation of taeniid ova, and some criteria of their viability. Annals of Tropical Medicine and Parasitology 48, 207–15.

L. J. Thomas & B. B. Babero (1956). Observations on the infectivity of Echinococcus eggs obtained from foxes (Alopex lagopus Linn.) on St. Lawrence Island, Alaska. Journal of Parasitology 42, 659.

T. M. Wachira , C. N. L. Macpherson & J. M. Gathuma (1991). Release and survival of Echinococcus multilocularis eggs in different environments in Turkana, and their possible impact on the incidence of hydatidosis in man and livestock. Journal of Helminthology 65, 5561.

J. F. Williams & C. W. Colli (1972). Influence of ionizing irradiation on infectivity of eggs of Echinococcus granulosus in laboratory rodents. Journal of Parasitology 58, 427–30.

Recommend this journal

Email your librarian or administrator to recommend adding this journal to your organisation's collection.

  • ISSN: 0031-1820
  • EISSN: 1469-8161
  • URL: /core/journals/parasitology
Please enter your name
Please enter a valid email address
Who would you like to send this to? *



Altmetric attention score

Full text views

Total number of HTML views: 0
Total number of PDF views: 36 *
Loading metrics...

Abstract views

Total abstract views: 360 *
Loading metrics...

* Views captured on Cambridge Core between September 2016 - 24th September 2017. This data will be updated every 24 hours.