Hostname: page-component-78c5997874-4rdpn Total loading time: 0 Render date: 2024-11-14T21:26:09.005Z Has data issue: false hasContentIssue false
  • English
  • Français

Comparison of the transmissibility of Trypanosoma congolense strains, isolated in a trypanosomiasis endemic area of eastern Zambia, by Glossina morsitans morsitans

Published online by Cambridge University Press:  24 May 2006

J. MASUMU ,
T. MARCOTTY ,
N. NDELEDJE ,
C. KUBI ,
S. GEERTS ,
J. VERCRUYSSE ,
P. DORNY  and
P. VAN DEN BOSSCHE
J. MASUMU
Affiliation:
Institute of Tropical Medicine, Animal Health Department, Nationalestraat 155, B-2000 Antwerp, Belgium
T. MARCOTTY
Affiliation:
Institute of Tropical Medicine, Animal Health Department, Nationalestraat 155, B-2000 Antwerp, Belgium
N. NDELEDJE
Affiliation:
Institute of Tropical Medicine, Animal Health Department, Nationalestraat 155, B-2000 Antwerp, Belgium
C. KUBI
Affiliation:
Institute of Tropical Medicine, Animal Health Department, Nationalestraat 155, B-2000 Antwerp, Belgium
S. GEERTS
Affiliation:
Institute of Tropical Medicine, Animal Health Department, Nationalestraat 155, B-2000 Antwerp, Belgium
J. VERCRUYSSE
Affiliation:
Ghent University, Vakgroep Virologie, Parasitologie en Immunologie, Salisburylaan 133, B-9820 Merelbeke, Belgium
P. DORNY
Affiliation:
Institute of Tropical Medicine, Animal Health Department, Nationalestraat 155, B-2000 Antwerp, Belgium Ghent University, Vakgroep Virologie, Parasitologie en Immunologie, Salisburylaan 133, B-9820 Merelbeke, Belgium
P. VAN DEN BOSSCHE
Affiliation:
Institute of Tropical Medicine, Animal Health Department, Nationalestraat 155, B-2000 Antwerp, Belgium University of Pretoria, Department of Veterinary Tropical Diseases, Onderstepoort, South Africa
Get access Rights & Permissions [Opens in a new window]

Abstract

Transmission experiments were conducted to compare the transmissibility of genetically different Trypanosoma congolense (Savannah subgroup) strains isolated from cattle in a trypanosomiasis endemic area of eastern Zambia. A total of 17 strains were compared. Three strains were extremely virulent with a short pre-patent period, high parasitaemia and a short median survival time (between 5 and 9 days) in mice. The remainder of the strains belonged to the moderate (6 strains) or low (8 strains) virulence categories with median survival times between 10 and 30 days and >30 days, respectively. Batches of 40 teneral Glossina morsitans morsitans (Diptera: Glossinidae) were offered a single bloodmeal on mice infected with one of those strains. Flies were dissected to determine their infection status 21 days later. The proportion of flies with procyclic and metacyclic infections differed significantly between trypanosome strains and were significantly higher in flies infected with extremely virulent strains (P=0·033 and P=0·016 for the differences in the procyclic infection rate of strains with moderate and low virulence, respectively and P=0·005 and P=0·019 for the differences in the metacyclic infection rate of strains with moderate and low virulence, respectively). On the other hand, moderately virulent strains had, in general, higher procyclic and metacyclic infection rates compared to low virulent strains. But the differences were not significant (P>0·05). The outcome of those experiments shows clear differences in transmissibility of trypanosome strains associated with their virulence. This observation confirms the theory for the evolution and maintenance of virulence in a parasite population and may explain the persistence of virulent trypanosome strains in a susceptible host population.

Keywords

Trypanosoma congolenseGlossina morsitans morsitanstransmissionvirulenceZambia
Type
Research Article
Information
Parasitology , Volume 133 , Issue 3 , September 2006 , pp. 331 - 334
Copyright
2006 Cambridge University Press

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

Aksoy, S., Gibson, W. C. and Lehane, M. J. ( 2003). Interactions between tsetse and trypanosomes with implications for the control of trypanosomiasis. Advances in Parasitology 53, 1–83.CrossRefGoogle Scholar
Anderson, R. M. and May, R. M. ( 1982). Coevolution of hosts and parasites. Parasitology 85, 411–426.CrossRefGoogle Scholar
Bengaly, Z., Sidibe, I., Ganaba, R., Desquesnes, M., Boly, H. and Sawadogo, L. ( 2002 a). Comparative pathogenicity of three genetically distinct types of Trypanosoma congolense in cattle: clinical observations and haematological changes. Veterinary Parasitology 108, 1–19.Google Scholar
Bengaly, Z., Sidibe, I., Boly, H., Sawadogo, L. and Desquesnes, M. ( 2002 b). Comparative pathogenicity of three genetically distinct Trypanosoma congolense-types in inbred Balb/c mice. Veterinary Parasitology 105, 111–118.Google Scholar
Dale, C., Welburn, S. C., Maudlin, I. and Milligan, P. J. M. ( 1995). The kinetics of maturation of trypanosome infections in tsetse. Parasitology 111, 187–191.CrossRefGoogle Scholar
Elsen, P., Van Hees, J. and De Lil, E. ( 1993). L'historique et les conditions d'élevage des lignées de glossines (Diptera, Glossinidae) maintenues à l'Institut de Médecine tropicale Prince Léopold d'Anvers. Journal of African Zoology 107, 439–449.Google Scholar
Herbert, W. J. and Lumsden, W. H. R. ( 1976). Trypanosoma brucei. A rapid “matching” method for estimating the host's parasitaemia. Experimental Parasitology 40, 427–431.Google Scholar
Leak, S. G. A. ( 1998). Tsetse Biology and Ecology: their Role in the Epidemiology and Control of Trypanosomosis. CABI Publishing, Wallingord Oxon.
Lloyd, L. L. and Johnson, W. B. ( 1924). The trypanosome infections of tsetse flies in Northern Nigeria and a method of estimation. Bulletin of Entomological Research 14, 225–227.Google Scholar
Masumu, J., Marcotty, T., Geysen, D., Geerts, S., Vercruysse, J., Dorny, P. and Van den Bossche, P. ( 2006 a). Comparison of the virulence of Trypanosoma congolense strains isolated from cattle in a trypanosomiasis endemic area of eastern Zambia. International Journal for Parasitology (in the Press).Google Scholar
Masumu, J., Geysen, D., Vansnick, E., Geerts, S. and Van den Bossche, P. ( 2006 b). A modified AFLP for Trypanosoma congolense isolate characterization. Journal of Biotechnology (in the Press).Google Scholar
Maudlin, I., Dukes, P., Luckins, A. G. and Hudson, K. M. ( 1986). Extrachromosomal inheritance of susceptibility to trypanosome infection in tsetse flies II. Susceptibility of selected lines of Glossina morsitans morsitans to different stocks and species of trypanosome. Annals of Tropical Medicine and Parasitology 80, 97–105.Google Scholar
Moloo, S. K. and Kutuza, S. B. ( 1988). Comparative study on the infection rates of different laboratory strains of Glossina species by Trypanosoma congolense. Medical and Veterinary Entomology 2, 253–257.CrossRefGoogle Scholar
Reifenberg, J. M., Cuisance, D., Frezil, J. L., Cuny, G. and Duvallet, G. ( 1997). Comparison of the susceptibility of different Glossina species to simple and mixed infections with Trypanosoma (Nannomomas) congolense savannah and riverine forest types. Medical and Veterinary Entomology 11, 246–252.CrossRefGoogle Scholar
STATACORP ( 2003). Stata Statistical Software: Release 8.0. Stata Corporation, Texas.
Van den Abbeele, J., Claes, Y., Van Bockstaele, D., Le Ray, D. and Coosemans, M. ( 1999). Trypanosoma brucei spp. development in the tsetse fly: characterization of the post-mesocyclic stages in the foregut and proboscis. Parasitology 118, 469–478.Google Scholar
Van den Bossche, P. and Staak, C. ( 1997). The importance of cattle as a food source for Glossina morsitans morsitans Westwood (Diptera: Glossinidae) in Katete District, Eastern Province, Zambia. Acta Tropica 65, 105–109.CrossRefGoogle Scholar
Wijers, D. J. and Willett, K. C. ( 1960). Factors that may influence the infection rate of Glossina palpalis with Trypanosoma gambiense. II. The number and morphology of the trypanosomes present in the blood of the host at the time of the infected feed. Annals of Tropical Medicine and Parasitology 54, 341–350.Google Scholar