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Further studies on bluetongue and bluetongue-related Orbiviruses in the Sudan

Published online by Cambridge University Press:  15 May 2009

M. E. H. Mohammed
Affiliation:
AFRC Institute for Animal Health, Pirbright Laboratory, Pirbright, Woking, Surrey GU24 ONF
P. S. Mellor
Affiliation:
AFRC Institute for Animal Health, Pirbright Laboratory, Pirbright, Woking, Surrey GU24 ONF
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Summary

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The seasonal incidence of bluetongue virus (BTV) in Central Sudan is related primarily to fluctuations in the prevalence of the vector, Culicoides imicola. Population densities of this midge begin to rise with the onset of precipitation and peak during October, before falling sharply at the end of the rainy season in November. These are also the months of BTV transmission. Populations of C. schultzei, the commonest midge in Central Sudan, are also related to the rainy season but this species does not seem to be involved with BTV transmission.

BTV serotype 2 was isolated from C. imicola confirming the status of this midge as a known vector but a second isolate of the same serotype was made from a mixed pool of Culicoides not including C. imicola. This suggests that BTV transmission in the Sudan may involve more than one species of Culicoides. Epizootic haemorrhagic disease virus (EHDV) serotype 4 and a palyam virus were isolated from C. schultzei which indicates that this species may be involved in the transmission of BT-related viruses. Seven further virus isolates from sentinel calves at Shambat (Khartoum) confirmed the presence of BTV serotypes 1, 4 and 16, and an untyped EHDV (designated 318) in the Sudan. All of the viruses isolated and identified during the course of this work are recorded from the Sudan for the first time.

Type
Research Article
Copyright
Copyright © Cambridge University Press 1990

References

REFERENCES

1.Mohammed, MEH, Taylor, WP. Infection with bluetongue and related orbiviruses in the Sudan detected by the study of sentinel calf herds. Epidemiol Infect 1987; 99: 533–45.Google Scholar
2.Service, MW. A battery operated light-trap for sampling mosquito populations. Bull the Wld Hlth Org 1970; 43: 635–41.Google ScholarPubMed
3.Mellor, PS, Osborne, R, Jennings, DM. Isolation of bluetongue and related viruses from Culicoides spp. in the Sudan. J Hyg 1984; 93: 621–8.Google Scholar
4.Herniman, KAJ, Gumm, ID, Owen, L, Taylor, WP, Sellers, RF. Distribution of bluetongu viruses and antibodies in some countries of the Eastern hemisphere. Bull d'Off Int de Epizoot 1980; 92: 581–6.Google Scholar
5.Mohammed, MEH. Epidemiological studies on some Sudanese arboviruses. [PhD Thesis] Reading, University of Reading 1988, 235 pp.Google Scholar
6.Lefevre, PC, Taylor, WP. Situation épidemiologique de le fiévre catarrhale du moutoi (bluetongue) ou Sénégal. Rev Elev Méd Vét Pays Trop 1983; 36: 241–5.Google Scholar
7.Karber, G. Beitrag zur kollektiven Behandlung pharmakologischer Reihenverssusche. Archiv Exp Path Pharm 1931; 162: 480–7.Google Scholar
8.Anderson, J. Use of monoclonal antibody in a blocking ELISA to detect group specific antibodies to bluetongue virus. J Immunol Meth; 1984; 74: 139–9.Google Scholar
9.Boorman, JPT, Mellor, P. Notes on Culicoides (Diptera, Ceratopogonidae) from the Sudan in relation to the epidemiology of bluetongue virus disease. Rev Elev Méd Vét Pays Trop 1982; 35: 173–8.Google Scholar
10.Mellor, PS, Pitzolis, G. Observations on breeding sites and light-trap collections of Culicoides during an outbreak of bluetongue in Cyprus. Bull of Ent 1979; 69: 229–34.Google Scholar
11.Du Toit, RM. The transmission of bluetongue and horse sickness by Culicoides. Onders J Ve Sci Anim Ind 1944; 19: 716.Google Scholar
12.Walker, AR, Davies, FG. A preliminary survey of the epidemiology of bluetongue in Kenya. J Hyg C 1971; 69: 4760.Google Scholar
13.Mellor, PS. The replication of bluetongue virus in Culicoides vectors. Curr Top Microbic Immunol 1990, 162; 143–61.Google Scholar