Hostname: page-component-cd9895bd7-dk4vv Total loading time: 0 Render date: 2024-12-28T05:09:22.475Z Has data issue: false hasContentIssue false

A verandah-trap hut for studying the house-frequenting habits of mosquitoes and for assessing insecticides. IV. The effect of tetramethrin on the behaviour and mortality of Anopheles gambiae Giles

Published online by Cambridge University Press:  10 July 2009

A. Smith
Affiliation:
Tropical Pesticides Research Institute, Arusha, Tanzania
P. I. M. Chabeda
Affiliation:
Tropical Pesticides Research Institute, Arusha, Tanzania

Extract

The effects of tetramethrin on the behaviour and mortality of Anopheles gambiae Giles entering verandah-trap huts have been studied with the assistance of gaschromatographic techniques.

Fifty-three to 39% of A. gambiae were deterred from entering a corrugated-iron-roof hut treated indoors with a nominal dosage of 2 gm/m2 tetramethrin active ingredient.

Overall mortalities were 53–71% in the first month of application, but fell two to three months after application to 22–46%.

The tetramethrin deposit had marked effects on the behaviour of A. gambiae entering treated huts. Feeding was greatly inhibited, 69–90% of the mosquitoes being unfed. Also, as the residual toxicity of the deposit declined, increasingly higher proportions (40–70%) of recently blood-fed A. gambiae left the huts due to the irritant action of the insecticide. The chemical basis of the irritant effect was indicated to the extent that survivors leaving the treated hut showed 9·5–14·0 ng tetramethrin/individual. The minimum lethal dose was indicated by 17·5–21·7 ng/individual picked up by mosquitoes showing delayed mortalities after leaving the treated huts. Mosquitoes that died indoors picked up amounts ranging from 27·0 to 42·3 ng/individual.

The effects of tetramethrin on A. gambiae were in general similar to those of DDT and pyrethrum, and differed only in degree.

Type
Original Articles
Copyright
Copyright © Cambridge University Press 1969

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

Maciver, D. R. (1964). Mosquito coils. Part II. Studies on the action of mosquito coil smoke on mosquitoes.—Pyrethrum Post 7 no. 3, 714.Google Scholar
Smith, A. (1965 a). A verandah-trap hut for studying the house-frequenting habits of mosquitos and for assessing insecticides. I.—A description of the verandah-trap hut and of studies on the egress of Anopheles gambiae Giles and Mansonia uniformis (Theo.) from an untreated hut.—Bull. ent. Res. 56, 161167.CrossRefGoogle Scholar
Smith, A. (1965 b). A verandah-trap hut for studying the house-frequenting habits of mosquitos and for assessing insecticides. II.—The effect of dichlorvos (DDVP) on egress and mortality of Anopheles gambiae Giles and Mansonia uniformis (Theo.) entering naturally.—Bull. ent. Res. 56, 275282.CrossRefGoogle Scholar
Smith, A. & Esozed, S. (1966). Studies on the efficiency of collecting and counting Anopheles gambiae in verandah-trap huts.—Misc. Rep. trop. Pestic. Res. Inst. no. 563, 13 pp., multigraph.Google Scholar
Smith, A. & Hocking, K. S. (1962). Assessment of the residual toxicity to Anopheles gambiae of the organophosphorus insecticides malathion and Baytex. Bull. Wld Hlth Org. 27, 231238.Google ScholarPubMed
Smith, A. & Obudho, W. O. (1967). Trials with pyrethrum mosquito coils against Anopheles gambiae entering a verandah-trap hut.—Pyrethrum Post 9 no. 2, 1517.Google Scholar
Smith, A. & Webley, D. J. (1969). A verandah-trap hut for studying the house-frequenting habits of mosquitoes and for assessing insecticides. III. The effect of DDT on behaviour and mortality.—Bull. ent. Res. 59, 3346.CrossRefGoogle Scholar
Yamamoto, I. & Casida, J. E. (1966). O-Demethyl pyrethrin II analogs from oxidation of pyrethrin I, allethrin, dimethrin, and phthalthrin by house fly enzyme system.—J. econ. Ent. 59, 15421543.CrossRefGoogle Scholar
de Zulueta, J. & Cullen, J. R. (1963). Deterrent effect of insecticides on malaria vectors.—Nature, Lond. 200 no. 4909, 860861.CrossRefGoogle Scholar