Effect of Essential Oils of Six Local Plants Used Insecticide on Adults of Anopheles gambiae, Giles 1902

Abstract Objective In the framework of EVALMOUS study aiming to assess the use and effectiveness of mosquito nets by pregnant women and other members of their household in a lagoon area in southern Benin, the behaviour of pregnant women relative to the time they go to bed using the net were recorded. Malaria vectors biting rhythm, Plasmodium falciparum infection and insecticide resistance genes in malaria vectors were also determined. Results Overall, 3848 females of Anopheles gambiae s. l were collected and 280 pregnant women responded to the survey. Almost all Anopheles gambiae s. l. tested were Anopheles coluzzi Coetzee and Wilkerson 2013 (Diptera: Culicidae). The CSP index in malaria vector was 1.85% and the allelic frequency of kdr gene was 74.4%. Around 90% of bites and Plasmodium falciparum Welch, 1897 (Haemosporida: Plasmodiidae) transmission occurred between 10 p.m. and 6 a.m., which coincides with the period when more than 80% of pregnant women were under bednet. Despite a slight early evening and early morning biting activity of malaria vectors in the study area, the good use of nets might remain a useful protection tool against mosquito biting and malaria transmission.

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Studies of House Leaving and Outside Resting of Anopheles gambiae Giles and Anopheles funestus Giles in East Africa. I.—The Outside Resting Population

Bulletin of Entomological Research ◽

10.1017/s0007485300027188 ◽

1954 ◽

Vol 45 (2) ◽

pp. 361-373 ◽

Cited By ~ 42

Author(s):

M. T. Gillies

Keyword(s):

Anopheles Gambiae ◽

Anopheles Funestus ◽

Drastic Reduction ◽

Natural Conditions ◽

Resting Sites ◽

Lowland Area ◽

Set Up ◽

Anopheles Gambiae Giles ◽

Gravid Females ◽

Periodic Examination

The behaviour of Anopheles gambiae Giles and A. funestus Giles was studied under natural conditions in a lowland area of Tanganyika.Studies on the outside resting population were carried out by direct searching for natural resting sites, and by the use of artificial box shelters partly buried in the ground in shaded localities. Catches in these give a valid sample when set up at some distance from houses.Fed and gravid females comprised 67 per cent. of the outside resting gambiae population, the latter group being between 12 and 4·5 times as numerous as the former. Rather less than half the funestus females caught were unfed, the remainder of the population being mainly composed of gravid females.Precipitin tests on the small numbers of fed females caught outside were nearly all positive for man.The identification of gravid funestus females was confirmed by periodic examination of the eggs.Entry of females into outside shelters did not occur solely in the period around sunrise. An appreciable number of funestus females did not enter before 07.00 hours and this was particularly so in shaded shelters.The building of a hut in the vicinity of a box shelter caused a drastic reduction in the numbers of mosquitos resting in the latter.Outside biting activity in these two species is of negligible importance as a source of females resting outside.

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Age physiologique et cycle d'agressivité chez Anopheles gambiae Giles et A. funestus Giles dans la région de Bobo-Dioulasso (Haute-Volta) [Dipt. Culicidae]

Bulletin de la Société entomologique de France ◽

10.3406/bsef.1964.20758 ◽

1964 ◽

Vol 69 (5) ◽

pp. 110-121

Author(s):

J. Hamon ◽

S. Sales ◽

Jean-Paul Adam ◽

P. Grenier

Keyword(s):

Anopheles Gambiae ◽

Bobo Dioulasso ◽

Anopheles Gambiae Giles

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Characterizing Permethrin and Etofenprox Resistance in Two Common Laboratory Strains of Anopheles gambiae (Diptera: Culicidae)

Insects ◽

10.3390/insects9040146 ◽

2018 ◽

Vol 9 (4) ◽

pp. 146 ◽

Cited By ~ 3

Author(s):

Aaron Gross ◽

Jeffrey Bloomquist

Keyword(s):

Anopheles Gambiae ◽

Pyrethroid Resistance ◽

Laboratory Strain ◽

Pyrethroid Insecticide ◽

Sub Saharan Africa ◽

Cross Resistance ◽

Type I ◽

Mosquito Vector ◽

Sub Saharan ◽

Anopheles Gambiae Giles

Anopheles gambiae Giles (Diptera: Culicidae) is the most prolific malaria vector in sub-Saharan Africa, where widespread insecticide resistance has been reported. An. gambiae laboratory strains are commonly used to study the basic biology of this important mosquito vector, and also in new insecticide discovery programs, where insecticide-susceptible and -resistant strains are often used to screen new molecules for potency and cross-resistance, respectively. This study investigated the toxicity of permethrin, a Type-I pyrethroid insecticide, and etofenprox, a non-ester containing pyrethroid insecticide, against An. gambiae at three life stages. This characterization was performed with susceptible (G3; MRA-112) and resistant (Akdr; MRA-1280) An. gambiae strains; the Akdr strain is known to contain the L1014F mutation in the voltage-sensitive sodium channel. Surprisingly, etofenprox displays a lower level of resistance than permethrin against all stages of mosquitoes, except in a headless larval paralysis assay designed to minimize penetration factors. In first-instar An. gambiae larvae, permethrin had significant resistance, determined by the resistance ratio (RR50 = 5), but etofenprox was not significantly different (RR50 = 3.4) from the wild-type strain. Fourth-instar larvae displayed the highest level of resistance for permethrin (RR50 = 108) and etofenprox (RR50 = 35). Permethrin (PC50 = 2 ppb) and etofenprox (PC50 = 9 ppb) resulted in headless larval paralysis (5-h), but resistance, albeit lower, was still present for permethrin (RR50 = 5) and etofenprox (RR50 = 6.9). In adult female mosquitoes, permethrin displayed higher resistance (RR50 = 14) compared to etofenprox (RR50 = 4.3). The level of etofenprox resistance was different from that previously reported for a similar Akron An. gambiae laboratory strain (MRA-913). The chemical synergists piperonyl butoxide (PBO) and diethyl maleate (DEM) were able to synergize permethrin, but not etofenprox in the resistant strain (Akdr). In conclusion, multiple mechanisms are likely involved in pyrethroid resistance, but resistance profiles are dependent upon selection. Etofenprox is an effective insecticide against An. gambiae in the lab but will likely suffer from resistance in the field.

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