Hostname: page-component-586b7cd67f-t7czq Total loading time: 0 Render date: 2024-11-23T22:40:24.686Z Has data issue: false hasContentIssue false

Transmission of Schistosoma mansoni from man to snail: experimental studies of miracidial survival and infectivity in relation to larval age, water temperature, host size and host age

Published online by Cambridge University Press:  06 April 2009

R. M. Anderson
Affiliation:
Department of Pure and Applied Biology, Imperial College, London University, London SW7 2BB
J. G. Mercer
Affiliation:
Department of Pure and Applied Biology, Imperial College, London University, London SW7 2BB
R. A. Wilson
Affiliation:
Biology Department, University of York, Heslington, York YOl 5DD
N. P. Carter
Affiliation:
Biology Department, University of York, Heslington, York YOl 5DD

Summary

We report the results of experimental work on (a) the influence of temperature on the age-dependent survival and infectivity of the mira-cidia of Schistosoma mansoni and (b) the relationship between snail age, snail size and susceptibility to infection. The death rate of miracidia declined exponentially with age where life-expectancy was maximal (approximately 16 h) at 15 °C. Infectivity also declined rapidly with larval age but, in contrast to larval survival, the rate of infection was at a maximum at 25 °C. Snail susceptibility was shown to be more closely correlated with host size rather than host age. Susceptibility declined exponentially with increased host size. Size-dependent susceptibility was shown to generate concave age-prevalence curves for infection within snail populations, where the maximum prevalence is generated in snails of intermediary age. Simple mathematical models are developed to aid estimation of larval survival and infection rates and experimental results are discussed in relation to the overall transmission success of the parasite from man to snail.

Type
Research Article
Copyright
Copyright © Cambridge University Press 1982

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

Anderson, R. M. (1978). Population dynamics of snail infection by miracidia. Parasitology 77, 201–24.Google Scholar
Anderson, R. M. & May, R. M. (1979 a). Prevalence of schistosome infections within molluscan populations: observed patterns and theoretical predictions. Parasitology 79, 6394.CrossRefGoogle ScholarPubMed
Anderson, R. M. & May, R. M. (1979 b). Population biology of infectious diseases. Part I. Nature, London 280, 361–7.CrossRefGoogle ScholarPubMed
Anderson, R. M. & Whitfield, P. J. (1975). Survival characteristics of the free-living cercarial populations of the ectoparasitic digenean Transversotrema patialense. Parasitology 70, 295310.CrossRefGoogle Scholar
Ansari, N. (1973). Epidemiology and Control of Schistosomiasis (Bilharziasis). Basel: S. Karger.Google Scholar
Barbour, A. D. (1978). Macdonald's model and the transmission of bilharzia. Transactions of the Royal Society of Tropical Medicine and Hygiene 72, 615.CrossRefGoogle ScholarPubMed
Bayne, C. J. & Kime, J. B. (1970). In vivo removal of bacteria from the haemolymph of the land snail Helix pomatia (Pulmonata Sylommatophora). Malacological Review 3, 103–13.Google Scholar
Chernin, E. (1968). Interference with the capacity of S. mansoni miracidia to infect the molluscan host. Journal of Parasitology 54, 509–16.CrossRefGoogle Scholar
Chernin, E. (1970). Behavioural responses of miracidia of Schistosoma mansoni and other trematodes to substances emitted by snails. Journal of Parasitology 56, 287–96.CrossRefGoogle ScholarPubMed
Chernin, E. (1972). Penetrative activity of Schistosoma mansoni miracidia stimulated by exposure to snail-conditioned water. Journal of Parasitology 58, 209–12.CrossRefGoogle ScholarPubMed
Cohen, J. E. (1973). Selective host mortality in a catalytic model applied to schistosomiasis. American Naturalist 107, 199212.CrossRefGoogle Scholar
De Witt, W. B. (1955). Influence of temperature on penetration of snail hosts by S. mansoni miracidia. Experimental Parasitology 4, 271–6.CrossRefGoogle Scholar
Faust, E. C. & Hoffman, W. A. (1934). Studies on Schistosomiasis mansoni in Puerto Rico. III. Biological studies 1. The extra-mammalian phases of the life cycle. Puerto Rico Journal of Public Health and Tropical Medicine 10, 147.Google Scholar
Lackie, A. M. (1980). Invertebrate immunity. Parasitology 80, 393412.CrossRefGoogle ScholarPubMed
MacDonald, G. (1965). The dynamics of helminth infections with special reference to schistosomes. Transactions of the Royal Society of Tropical Medicine and Hygiene 59, 489506.Google Scholar
MacInnis, A. J., Bethel, W. M. & Cornford, E. M. (1974). Identification of chemicals of snail origin that attract Schistosoma mansoni miracidia. Nature, London 248, 301–3.Google Scholar
Maldonado, J. & Acosta-Matienzo, J. (1948). Biological studies on the miracidia of S. mansoni. American Journal of Tropical Medicine 28, 645–57.Google Scholar
Maramorosch, K. & Shope, R. F. (1975). Invertebrate Immunity. New York: Academic Press.Google Scholar
Mason, P. R. (1977). Stimulation of the activity of Schistosoma mansoni miracidia by snail-conditioned water. Parasitology 75, 325–38.Google Scholar
May, R. M. (1977). Togetherness among schistosomes: its effects on the dynamics of the infection. Mathematical Biosciences 35, 301–13.CrossRefGoogle Scholar
May, R. M. & Anderson, R. M. (1979). Population biology of infectious diseases. Part II. Nature, London 280, 455–61.Google Scholar
Nasell, I. & Hirsch, W. M. (1973). The transmission dynamics of schistosomiasis. Communications in Pure and Applied Mathematics 26, 395453.Google Scholar
Pesigan, T. P., Hairston, N. G., Jaurequi, J. J., Garcia, E. G., Santos, A. T., Santos, B. C. & Besa, A. A. (1958). Studies on Schistosoma japonicum infection in the Philippines. 2. The molluscan host. Bulletin of the World Health Organization 27, 171–81.Google Scholar
Prah, S. K. & James, C. (1977). The influence of physical factors on the survival and infectivity of miracidia of Schistosoma mansoni and S. haematobium. I. Effect of temperature and ultra-violet light. Journal of Helminthology 51, 7385.CrossRefGoogle ScholarPubMed
Purnell, R. E. (1966). Host–parasite relationships in schistosomiasis. I. The effect of temperature on the infection of B. sud. tanganyiensis with S. mansoni miracidia and of laboratory mice with S. mansoni cercariae. Annals of Tropical Medicine and Parasitology 60, 90–6.Google Scholar
Shiff, C. J. & Kriel, R. L. (1970). A water soluble product of Bulinus (Physopsis) globosus attractive to Schistosoma haematobium miracidia. Journal of Parasitology 56, 281–6.CrossRefGoogle ScholarPubMed
Smithers, S. R. & Terry, R. J. (1965). The infection of laboratory hosts with cercariae of Schistosoma mansoni and the recovery of adult worms. Parasitology 55, 695700.CrossRefGoogle ScholarPubMed
Standen, O. D. (1952). Experimental infection of Australorbis glabratus with S. mansoni. I. Individual and mass infection of snails and the relationship of infection to temperature and season. Annals of Tropical Medicine and Parasitology 46, 4856.Google Scholar
Stirewalt, M. A. (1954). Effect of snail maintenance temperature on development of S. mansoni. Experimental Parasitology 3, 504–11.Google Scholar
Sturrock, R. F. (1973). Field studies on the transmission of Schistosoma mansoni and on the bionomics of its intermediate host, Biomphalaria glabrata, on St. Lucia, West Indies. International Journal of Parasitology 3, 175–94.CrossRefGoogle Scholar
Sturrock, R. F. & Upatham, E. S. (1973). An investigation of the interactions of some factors influencing the infectivity of Schistosoma mansoni miracidia to Biomphalaria glabrata. International Journal for Parasitology 3, 3541.CrossRefGoogle ScholarPubMed
Sturrock, R. F., Cohen, J. E. & Webbe, G. (1975). Catalytic curve analysis of schistosomiasis in snails. Annals of Tropical Medicine and Parasitology 69, 133–4.CrossRefGoogle ScholarPubMed
Sturrock, R. F. & Webbe, G. (1971). The application of catalytic models to schistosomiasis in snails. Journal of Helminthology 45, 189200.Google Scholar
Thomas, J. D. (1973). Schistoso miasis and the control of molluscan hosts of human schistosomiasis with particular reference to possible self-regulatory mechanisms. Advances in Parasitology 11, 307–94.Google Scholar
Thomas, J. D., Benjamin, M., Lough, A. & Aram, R. H. (1974). The effects of calcium in the external environment on growth and natality rates of Biomphalaria glabrata (Say). Journal of Animal Ecology 43, 839–60.Google Scholar
Upatham, E. S. (1972). Effects of some physico-chemical factors on the infection of Biomphalaria glabrata (Say) by miracidia of Schistosoma mansoni Sambon in St. Lucia, West Indies. Journal of Helminthology 4, 307–15.Google Scholar
Webbe, G. (1962). The transmission of Schistosoma haematobium in an area of Lake Province Tanganyika. Bulletin of the World Health Organization 27, 5985.Google Scholar
Wen, S. T. (1962). The behaviour of the free-living stages of the larvae – miracidium and cercaria – of S. mansoni and S. haematobium, with special reference to their modes of host finding and host penetration. Ph.D. thesis, University of London.Google Scholar