Hostname: page-component-586b7cd67f-r5fsc Total loading time: 0 Render date: 2024-11-30T17:14:42.656Z Has data issue: false hasContentIssue false
  • English
  • Français

A veranda-trap hut for studying the house-frequenting habits of mosquitoes and for assessing insecticides. III. The effect of DDT on behaviour and mortality

Published online by Cambridge University Press:  10 July 2009

A. Smith  and
D. J. Webley
A. Smith
Affiliation:
Tropical Pesticides Research Institute, Arusha, Tanzania
D. J. Webley
Affiliation:
Tropical Pesticides Research Institute, Arusha, Tanzania
Get access Rights & Permissions [Opens in a new window]

Extract

The effects of DDT on the behaviour and mortality of Anopheles gambiae Giles, A. funestus Giles, Mansonia uniformis (Theo.) and Culex pipiens fatigans Wied., entering experimental huts, have been studied with the assistance of gas-chromatographic techniques.

Sixty to 70% of A. gambiae and 70–80% of M. uniformis were deterred from entering verandah-trap huts treated indoors with a nominal dosage of 200 μg/cm2 of DDT active ingredient. Gas chromatographic techniques indicate that the chemical basis of the deterrency was a steadily diminishing outflow of DDT from the hut, either as a dust or vapour, and the build-up of deposit on the untreated overhanging eaves to 0·02 to 0·27 μg/cm2 seven months after treatment. A. funestus was less deterred than A. gambiae and M. uniformis, but the behaviour of C. p. fatigans was almost unaffected by the DDT deposit.

Overall mortalities were highest in A. funestus and M. uniformis, lower in A. gambiae and extremely low in C. p. fatigans.

There was a marked irritant effect of the DDT deposit on recently blood-fed A. gambiae, some 50–70% being driven out of the treated huts. This behaviour occurred to a lesser degree in A. funestus but was absent in M. uniformis and C. p. fatigans. The chemical basis of the irritant effect was indicated to the extent that surviving mosquitoes, that left the treated hut, showed 1·5 ng/insect of DDT. Mosquitoes that died, whether indoors or after leaving the hut, picked up amounts ranging from 7 to 20 ng/insect.

Type
Original Articles
Information
Bulletin of Entomological Research , Volume 59 , Issue 1 , July 1969 , pp. 33 - 46
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

Muirhead-Thomson, R. C. (1947). The effects of house spraying with pyrethrum and with DDT on Anopheles gambiae and A. melas in West Africa.—Bull. ent. Res. 38, 449–464.CrossRefGoogle Scholar
Smith, A. (1963). Deterrent effect of insecticides on malaria vectors.—Nature, Lond. 200 no. 4909, 861–862.CrossRefGoogle 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, 161–167.Google 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.)—Bull. ent. Res. 56, 275–282.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, 231–238.Google ScholarPubMed
De Zulueta, J. & Cullen, J. R. (1963). Deterrent effect of insecticides on malaria vectors.—Nature, Lond. 200 no. 4909, 860–861.CrossRefGoogle Scholar