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First Results in the Control of Simulium damnosum Theobald (Diptera, Simuliidae) in Northern Nigeria

Published online by Cambridge University Press:  10 July 2009

R. W. Crosskey
R. W. Crosskey
Affiliation:
Entomologist, Simulium Control Unit, Ministry of Health, Northern Nigeria
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Extract

An experimental control project against Simulium damnosum Theo. in Northern Nigeria using DDT in diesel oil as a larvicide is described. A description, together with a map, is given of the project area, some 1,200 sq. miles in extent, with a population of 32,000 persons, and it is emphasised that this was selected to provide information on the feasibility of control in an area not isolated from other fly foci.

Methods used in applying the larvicide to the rivers, which had rocky beds with rapids and falls, and assessing the effects of treatment are discussed. Applications were made at prearranged treatment points, weekly, for a period of 12 weeks in the dry season of two successive years, 1956 and 1957, and the post-treatment density of adult fly was assessed and compared in a Table and in histograms, with that existing in the year prior to treatment.

In the first year, a mean dosage per application of 1·4 p.p.m. of p,p′DDT applied over 30 minutes (S.D. = 0·5 p.p.m.) at each of four treatment points resulted in the clearance of all breeding for a distance of 15–23 miles below these points, and a reduction of adult fly density in the area of 96 per cent. as compared with pre-treatment density. But reinfestation of cleared breeding grounds was found to be rapid, these becoming repopulated with immature stages within six months in spite of a mean wet-season fly density of only 0·35 flies per boy-hour.

In the second year, with application of 1 p.p.m. of p,p′DDT for 30 minutes, results were less successful than in the first, although three additional treatment points were used with the aim of controlling a greater distance than in the first year, adult density being only reduced by an estimated 82 per cent. of that before treatment in the first year. The reasons for this are discussed, and the lower degree of control is attributed to the partial failure of the insecticide to reach the breeding sites owing to the exceptionally low state of the rivers.

The fly-rounds used in assessing adult density and the pre-treatment breeding sites and the positions of the treatment points are shown on maps. Detailed data from the fly-rounds are given in an Appendix.

With the exception of slight mortality among fish, thought to be due to accidental impediments to tbfi free downstream flow of the larvicide, no toxic effects on other organisms were observed.

The cost of treatment is given, and the results are discussed briefly in relation to the existing knowledge on control of S. damnosum. It is suggested that control by the application of larvicides in non-isolated foci is a practicable possibility, but that annual treatment might be necessary because of rapid re-establishment in cleared areas. The effect of control, of the degree obtained in this work, on the incidence of human onchocerciasis cannot yet be determined.

Type
Research Paper
Information
Bulletin of Entomological Research , Volume 49 , Issue 4 , December 1958 , pp. 715 - 735
Copyright
Copyright © Cambridge University Press 1958

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References

Arnason, A. P., Brown, A. W. A., Fredeen, F. J. H., Hopewell, W. W. & Rempel, J. G. (1949). Experiments in the control of Simulium arcticum Malloch by means of DDT in the Saskatchewan River.—Sci. Agric., 29, pp. 527–537.Google Scholar
Barnley, G. R. (1953). The control of Simulium damnosum (Theobald) on the Victoria Nile, Uganda.—WHO/Onchocerciasis/18, multigraph.Google Scholar
Budden, F. H. (1955). Incidence of human infection with onchocerciasis in different communities in relation to the incidence and type of the ocular lesions.—Brit. J. Ophthal., 39, pp. 321–332.CrossRefGoogle Scholar
Budden, F. H. (1956). The epidemiology of onchocerciasis in Northern Nigeria.—Trans. R. Soc. trop. Med. Hyg., 50, pp. 366–378.CrossRefGoogle ScholarPubMed
Crisp, G. (1956). Simulium and onchocerciasis in the Northern Territories of the Gold Coast.—171 pp. London, H. K. Lewis.Google Scholar
Crosskey, R. W. (1956). The distribution of Simulium damnosum Theobald in Northern Nigeria.—Trans. R. Soc. trop. Med. Hyg., 50, pp. 379–892.CrossRefGoogle ScholarPubMed
Edwards, E. E. (1956). Human onchocerciasis in West Africa with special reference to the Gold Coast.—J. W. Afr. sci. Ass., 2, pp. 1–35.Google Scholar
Fairchild, G. B. & Barreda, E. A. (1945). DDT as a larvicide against Simulium.—J. econ. Ent., 38, pp. 694–699.CrossRefGoogle ScholarPubMed
Garnham, P. C. C. & McMahon, J. P. (1947). The eradication of Simulium neavei, Roubaud, from an onchocerciasis area in Kenya Colony.—Bull. ent. Res., 37, pp. 619–628.CrossRefGoogle ScholarPubMed
Gibbins, E. G. & Loewenthal, L. J. A. (1933). Cutaneous onchocerciasis in a Simulium damnosum-infested region of Uganda.—Ann. trop. Med. Parasit., 27, pp. 489–496.CrossRefGoogle Scholar
Gjullin, C. M., Cope, O. B., Quisenberry, B. F. & Duchanois, F. E. (1949). The effect of some insecticides on black fly larvae in Alaskan streams.—J. econ. Ent., 42, pp. 100–105.CrossRefGoogle ScholarPubMed
Gjullin, C. M., Cross, H. F. & Applewhite, K. H. (1950). Tests with DDT to control black fly larvae in Alaskan streams.—J. econ. Ent., 43, pp. 696–697.CrossRefGoogle Scholar
Gjullin, C. M., Sleeper, D. A. & Husman, C. N. (1949). Control of black fly larvae in Alaskan streams by aerial applications of DDT.—J. econ. Ent., 42, p. 392.CrossRefGoogle ScholarPubMed
Goulding, R. L. jr., & Deonier, C. C. (1950). Observations on the control and ecology of black flies in Pennsylvania.—J. econ. Ent., 43, pp. 702–704.CrossRefGoogle Scholar
Hocking, B. (1950). Further tests of insecticides against black flies (Diptera: Simuliidae) and a control procedure.—Sci. Agric., 30, pp. 489–508.Google Scholar
Hocking, B. (1953). Developments in the chemical control of black flies (Diptera: Simuliidae).—Canad. J. agric. Sci., 33, pp. 572–578.Google Scholar
Hocking, B. & Richards, W. E. (1952). Biology and control of Labrador black flies (Diptera: Simuliidae).—Bull. ent. Res., 43, pp. 237–257.CrossRefGoogle Scholar
Hocking, B., Twinn, C. E. & McDuffie, W. C. (1949). A preliminary evaluation of some insecticides against immature stages of blackflies (Diptera: Simuliidae).—Sci. Agric., 29, pp. 69–80.Google Scholar
Hughes, M. H. (1956). Some unsolved problems in onchocerciasis.—J. W. Afr. sci. Ass., 2, p. 101.Google Scholar
Jamnback, H. & Collins, D. L. (1955). The control of blackflies (Diptera: Simuliidae) in New York.—Bull. N.Y. St. Mus., no. 350, 113 pp.Google Scholar
Kindler, J. B. & Regan, P. E. (1949). Larvicide tests on blackflies in New Hampshire.—Mosq. News, 9, pp. 108–112.Google ScholarPubMed
Lea, A. O. jr., & Dalmat, H. T. (1954). Screening studies of chemicals for larval control of blackflies in Guatemala.—J. econ. Ent., 47, pp. 135–141.CrossRefGoogle Scholar
Lea, A. O. jr., & Dalmat, H. T. (1955 a). Field studies on larval control of black flies in Guatemala.—J. econ. Ent., 48, pp. 274–278.CrossRefGoogle Scholar
Lea, A. O. jr & Dalmat, H. T. (1955 b). A pilot study of area larval control of black flies in Guatemala.—J. econ. Ent., 48, pp. 378–383.CrossRefGoogle Scholar
Noel-Buxton, M. B. (1956). Field experiments with DDT in association with finely divided inorganic material for the destruction of the immature stages of the genus Simulium in the Gold Coast.—J. W. Afr. sci. Ass., 2, pp. 36–40.Google Scholar
Taufflieb, R. (1955). Une campagne de lutte centre Simulium damnosum au Mayo Kebbi.—Bull. Soc. Path. exot., 48, pp. 564–576.Google Scholar
Taufflieb, R. (1956). Rapport sur la campagne antisimulidienne de 1956 au Mayo-Kebbi.—Bull. Inst. centrafr., (N.S.) no. 11, pp. 53–59.Google Scholar
Travis, B. V., Collins, D. L., de Foliart, G. & Jamnback, H. (1951). Strip spraying by helicopter to control blackfly larvae.—Mosq. News, 11, pp. 95–98.Google Scholar
Twinn, C. R. (1950). Studies of the biology and control of biting flies in northern Canada.—Arctic, 3, pp. 14–26.CrossRefGoogle Scholar
Wanson, M. (1950). Contribution à l'étude de l'onchocercose africaine humaine.—Ann. Soc. belge Méd. trop., 30, pp. 667–863.Google Scholar
Wanson, M., Courtois, L. & Lebied, B. (1949). L'éradication du Simulium damnosum (Théobald) à Léopoldville.—Ann. Soc. beige Med. trop., 29, pp. 373–403.Google Scholar
World Health Organisation. (1954). Expert Committee on Onchocerciasis. First Report.—Tech. Rep. World Hlth Org., no. 87, 37 pp.Google Scholar