Skip to main content Accessibility help
×
Home
Hostname: page-component-7ccbd9845f-s2vjv Total loading time: 0.234 Render date: 2023-02-01T22:47:53.575Z Has data issue: true Feature Flags: { "useRatesEcommerce": false } hasContentIssue true

Release and survival of Echinococcus eggs in different environments in Turkana, and their possible impact on the incidence of hydatidosis in man and livestock

Published online by Cambridge University Press:  05 June 2009

T. M. Wachira
Affiliation:
University of Nairobi College of Agriculture and Veterinary Science, P.O. Box 29053, Kabete, Nairobi, Kenya
C. N. L. Macpherson
Affiliation:
University of Nairobi College of Agriculture and Veterinary Science, P.O. Box 29053, Kabete, Nairobi, Kenya Swiss Tropical Institute, Field Laboratory, P.O. Box 53, Ifakara, Tanzania
J. M. Gathuma
Affiliation:
University of Nairobi College of Agriculture and Veterinary Science, P.O. Box 29053, Kabete, Nairobi, Kenya

Abstract

In Turkana, Kenya, a prevalence of hydatidosis of nearly 10% has been recorded among the pastoralists yet their livestock have a much lower prevalence of the disease. The present study investigated the release from dogs and subsequent survival of Echinococcus eggs in Turkana huts, water-holes and in the semi-arid environment. The results were compared with the survival of eggs of Taenia hydatigena and T. saginata. The study was repeated under the cooler and moister conditons found in Maasailand where livestock have a greater incidence of hydatid disease than in Turkana but where the incidence in man is ten times lower. The average number of Echinococcus eggs per proglottid is 823. Nine percent of these remain in proglottids 15 minutes after release from a dog and the released eggs lose their viability in less than two, 48 and 300 hours in the sun, huts and water in Turkana respectively; the major influencing factor being temperature. The greater survival of eggs in the houses, coupled with the fact that dogs congregate for most of the day in the small houses facilitating a close man:dog contact, provide ideal conditions for the trasmission of the parasite to man. The hostile environmental conditions and lack of contact between dogs and livestock contributes to the lower infection rate in livestock. Conversely in Maasailand, Echinococcus eggs survive in the environment for longer than three weeks and in addition, dogs are used for herding. This partly explains the higher infection rate among Maasai livestock but the low human infection rate remains arcane and requires further study. The rapid mortality of the majority of Echinococcus eggs in Turkana suggests that control measures aimed at dog control and a decreased man:dog contact should have a profound effect on the incidence of the disease in an area intrinsically unsuitable for the parasites' survival.

Type
Research Papers
Copyright
Copyright © Cambridge University Press 1991

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

Coman, B. J. (1975) The survival of Taenia pisiformis eggs under laboratory conditions and the field environment. Australian Veterinary Journal, 51, 560565.CrossRefGoogle ScholarPubMed
Coman, B. J. & Rickard, M. D. (1975) The location of Taenia pisiformis, Taenia ovis and Taenia hydatigena in the gut of the dog and its effect on the environmental contamination with ova. Zeitschrift für Parasitenkunde, 47, 237248.CrossRefGoogle ScholarPubMed
Coman, B. J. & Rickard, M. D. (1977) A comparison of in vitro and in vivo estimates of the viability of Taenia pisiformis eggs aged under controlled conditions, and their ability to immunise against a challenge infection. International Journal for Parasitology, 7, 1522.CrossRefGoogle ScholarPubMed
Deve, F. (1910) [Echinococcose primitive experimentale. Resistance des oeufs du Taenia echinococque a la congelation.] Comptes Rendus des Séances de la Societé de Biologie 69, 568570.Google Scholar
Featherston, D. W. (1969) Taenia hydatigena. II. Growth and development of adult stage in the dog. Experimental Parasitology, 25, 329338.CrossRefGoogle Scholar
Gemmell, M. A. (1977) Taeniidae: Modification to the life span of the egg and the regulation of the tapeworm populations. Experimental Parasitology, 41, 314328.CrossRefGoogle ScholarPubMed
Gemmell, M. A. & Lawson, J. R. (1986) Epidemiology and control of hydatid disease. In: The biology of Echinococcus and hydatid disease, (Editor Thompson, R. C. A.) pp 199216. George Allen and Unwin, London.Google Scholar
Gemmell, M. A., Lawson, J. R. & Roberts, M. G. (1986) Population dynamics in echinococcosis and cysticercosis: biological parameters of Echinococcus granulosus in dogs and sheep. Parasitology, 92, 599620.CrossRefGoogle ScholarPubMed
Laws, G. F. (1968) Physical factors influencing survival of taeniid eggs. Experimental Parasitology, 22, 227239.CrossRefGoogle ScholarPubMed
Lawson, J. R. & Gemmell, M. A. (1983) Hydatidosis and cysticercosis: the dynamics of transmission. Advances in Parasitology, 22, 261308.CrossRefGoogle ScholarPubMed
Macpherson, C. N. L. (1981) Epidemiology and strain differentiation of Echinococcus granulosus in Kenya. PhD thesis, University of London.Google Scholar
Macpherson, C. N. L. (1985) Epidemiology of hydatid disease in Kenya: a study of the domestic intermediate hosts in Maasailand. Transactions of the Royal Society of Tropical Medicine and Hygiene, 79, 209217.CrossRefGoogle Scholar
Macpherson, C. N. L., French, C. M., Stevenson, P., Karstad, L. & Arundel, J. H. (1985) Hydatid disease in the Turkana District of Kenya, IV: The prevalence of Echinococcus granulosus infections in dogs, and observations on the role of the dog in the lifestyle of the Turkana. Annals of Tropical Medicine and Parasitology, 79, 5161.CrossRefGoogle ScholarPubMed
Macpherson, C. N. L., Romig, T., Zeyhle, E., Rees, P. H. & Were, J. B. O. (1987) Portable ultrasound scanner versus serology in screening for hydatid cysts in a nomadic population. Lancet, 11, 259261.CrossRefGoogle Scholar
Macpherson, C. N. L., Spoerry, A., Zeyhle, E., Thomas, T. & Gorfe, M. (1989) Pastoralists and hydatid disease: an ultrasound scanning prevalence survey in East Africa. Transactions of the Royal Society of Tropical Medicine and Hygiene, 83, 243247.CrossRefGoogle ScholarPubMed
Penfold, W. J., Penfold, H. B. & Philips, M. (1937) Taenia saginata: its growth and propagation. Journal of Helminthology, 15, 4148.CrossRefGoogle Scholar
Ross, I. C. (1929) Observations on the hydatid parasite (Echinococcus granulosus) and control of hydatid disease in Australia. Bulletin of the Council for Scientific and Industrial Research of Australia, 40, 163.Google Scholar
Schaefer, J. (1986) [Die uberlebensauer von Echinococcus multilocularis Eiern unter freiland-bedingungen und die moglichkeit ihrer verschleppung durch evertebraten.] PH.D. thesis, University of Hohenheim, West Germany.Google Scholar
Schwabe, C. W. & Abou Daoud, K. (1981) Epidemiology of echinococcosis in the Middle East I; Human infection in Lebanon, 1949–1959. American Journal of Tropical Medicine and Hygiene, 10, 374381.CrossRefGoogle Scholar
Stevenson, P. (1983) Observations on the hatching and activation of fresh Taenia saginata eggs. Annals of Tropical Medicine and Parasitology, 77, 399404.CrossRefGoogle ScholarPubMed
Stevenson, P. & Macpherson, C. N. L. (1982) The recovery of cestode eggs from water and soil in the Turkana District of Kenya. In: Current Medical Research in Eastern Africa with an emphasis on Zoonoses and Waterborne Diseases, Proceedings of the Third Annual Scientific Conference of KEMRI and KETRI, Nairobi, Kenya, (editors, Tukei, P. M. and Njogu, A. R.). Africascience International, Nairobi, Kenya. p. 1315.Google Scholar
Suvorov, V. Y. (1965) On the viability of the oncospheres of Taenia saginata. Meditsinskaya Parasitologia i Parazitarnye Bolezni, 34, 98100.Google ScholarPubMed
Watson-Jones, D. L. & Macpherson, C. N. L. (1988) Hydatid disease in the Turkana district of Kenya VI. Man:dog contact and its role in the transmission and control of hydatidosis amongst the Turkana. Annals of Tropical Medicine and Parasitology, 82, 343356.CrossRefGoogle ScholarPubMed
51
Cited by

Save article to Kindle

To save this article to your Kindle, first ensure coreplatform@cambridge.org is added to your Approved Personal Document E-mail List under your Personal Document Settings on the Manage Your Content and Devices page of your Amazon account. Then enter the ‘name’ part of your Kindle email address below. Find out more about saving to your Kindle.

Note you can select to save to either the @free.kindle.com or @kindle.com variations. ‘@free.kindle.com’ emails are free but can only be saved to your device when it is connected to wi-fi. ‘@kindle.com’ emails can be delivered even when you are not connected to wi-fi, but note that service fees apply.

Find out more about the Kindle Personal Document Service.

Release and survival of Echinococcus eggs in different environments in Turkana, and their possible impact on the incidence of hydatidosis in man and livestock
Available formats
×

Save article to Dropbox

To save this article to your Dropbox account, please select one or more formats and confirm that you agree to abide by our usage policies. If this is the first time you used this feature, you will be asked to authorise Cambridge Core to connect with your Dropbox account. Find out more about saving content to Dropbox.

Release and survival of Echinococcus eggs in different environments in Turkana, and their possible impact on the incidence of hydatidosis in man and livestock
Available formats
×

Save article to Google Drive

To save this article to your Google Drive account, please select one or more formats and confirm that you agree to abide by our usage policies. If this is the first time you used this feature, you will be asked to authorise Cambridge Core to connect with your Google Drive account. Find out more about saving content to Google Drive.

Release and survival of Echinococcus eggs in different environments in Turkana, and their possible impact on the incidence of hydatidosis in man and livestock
Available formats
×
×

Reply to: Submit a response

Please enter your response.

Your details

Please enter a valid email address.

Conflicting interests

Do you have any conflicting interests? *