Hostname: page-component-78c5997874-s2hrs Total loading time: 0 Render date: 2024-11-10T12:48:25.905Z Has data issue: false hasContentIssue false

The kinetics of maturation of trypanosome infections in tsetse

Published online by Cambridge University Press:  06 April 2009

C. Dale
Affiliation:
Tsetse Research Group, University of Bristol, Department of Veterinary Medicine, Longford House, Longford, Bristol BS18 7DU Liverpool School of Tropical Medicine, Pembroke Place, Liverpool L3 5QA
S. C. Welburn
Affiliation:
Tsetse Research Group, University of Bristol, Department of Veterinary Medicine, Longford House, Longford, Bristol BS18 7DU
I. Maudlin
Affiliation:
Tsetse Research Group, University of Bristol, Department of Veterinary Medicine, Longford House, Longford, Bristol BS18 7DU
P. J. M. Milligan
Affiliation:
Liverpool School of Tropical Medicine, Pembroke Place, Liverpool L3 5QA

Summary

Estimates of the time delay between the infective bloodmeal and maturation (incubation or maturation time) for 4 trypanosome stocks (2 Trypanozoon and 2 Trypanosoma congolense) show that maturation time in tsetse is not a parasite species-specific constant. The mean incubation time of a Trypanosoma brucei rhodesiense stock (EATRO 2340 – 18 days) was not significantly different from one T. congolense stock (SIKUDA88 – 15·5 days) but was significantly greater than another (1/148 FLY9 – 12·5 days). There was no significant difference in incubation times between male and female Glossina morsitans morsitans for any of the stocks but in both of the Trypanozoon stocks the proportion of female flies producing mature infections was significantly less than in males. However, estimates of gene frequency, assuming a model in which maturation is controlled by an X-linked recessive allele, gave inconsistent results indicating that maturation cannot be controlled by a single sex-linked gene. Maturation was shown to be a tsetse sex-dependent phenomenon in Trypanozoon but not in T. congolense infections. Incubation time was quite variable even for a single trypanosome stock (e.g. standard deviation of 5 days for one Trypanozoon stock); we discuss how this variability can affect disease transmission, and the interpretation of age-prevalence data.

Type
Research Article
Copyright
Copyright © Cambridge University Press 1995

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

Buxton, P. A. (1955). The Natural History of Tsetse Flies. London, School of Hygiene and Tropical Medicine Memoir No. 10. H. K. Lewis, London.Google Scholar
Cornellisen, A. W. C. A., Bakkeren, G. A. M., Barry, J. D., Michels, A. M. & Borst, P. (1985). Characteristics of trypanosome variant antigen genes active in the tsetse fly. Nucleic Acids Research 13, 4661–76.CrossRefGoogle Scholar
Dukes, P., Kaukas, A., Hudson, K. M., Asonganyi, T. & Gashumba, J. K. (1989). A new method for isolating Trypanosoma brucei gambiense from sleeping sickness patients. Transactions of the Royal Society of Tropical Medicine and Hygiene 83, 636–9.CrossRefGoogle ScholarPubMed
Hargrove, J. W. (1991). Age dependent changes in the probabilities of survival and capture of tsetse, Glossina morsitans morsitans Westwood. Insect Science and its Application 11, 323–30.Google Scholar
Harley, J. (1966). Studies of age and trypanosome infection rate in females of Glossina pallidipes Aust., G. palpalis fuscipes Newst. and G. brevipalpis Newst. in Uganda. Bulletin of Entomological Research 57, 2337.CrossRefGoogle Scholar
Hoare, C. A. (1970). The mammalian trypanosomes of Africa. In The African Trypanosomiases (ed. Mulligan, H. W.), pp. 2459. London: George Allen and Unwin.Google Scholar
Maudlin, I., Welburn, S. C. & Milligan, P. (1991). Salivary gland infections: a sex linked recessive character in tsetse? Acta Tropica 48, 915.CrossRefGoogle Scholar
Tarimo, S. A., Snow, F. W., Butler, L. & Dransfield, R. (1985). The probability of tsetse acquiring trypanosome infection from single blood meal in different localities in Kenya. Acta Tropica 42, 199207.Google ScholarPubMed
Welburn, S. C. & Maudlin, I. (1987). A simple in vitro method for infecting tsetse with trypanosomes. Annals of Tropical Medicine and Parasitology 81, 453–5.CrossRefGoogle ScholarPubMed
Welburn, S. C. & Maudlin, I. (1991). Rickettsia-like organisms, puparial temperature and susceptibility to trypanosome infection in Glossina morsitans. Parasitology 102, 201–6.CrossRefGoogle ScholarPubMed
Welburn, S. C. & Maudlin, I. (1992). The nature of the teneral state in Glossina and its role in the acquisition of trypanosome infections in tsetse. Annals of Tropical Medicine and Parasitology 86, 529–36.CrossRefGoogle Scholar
Welburn, S. C. & Maudlin, I. (1994). Maturation of trypanosome infections in tsetse. Experimental Parasitology 79, 202–5.Google Scholar
Woolhouse, M. E. J., Hargrove, J. W. & McNamara, J. J. (1993). Epidemiology of trypanosome infections of the tsetse-fly Glossina pallidipes in the Zambezi valley. Parasitology 106, 479–85.CrossRefGoogle ScholarPubMed
Young, C. J. & Godfrey, D. G. (1983). Enzyme polymorphism and the distribution of Trypanosoma congolense isolates. Annals of Tropical Medicine and Parasitology 77, 467–81.CrossRefGoogle ScholarPubMed