Comparative study of the effect of solvents on the efficacy of neonicotinoid insecticides against malaria vector populations across Africa  

作　　者：Magellan Tchouakui Tatiane Assatse Leon M.J.Mugenzi Benjamin D.Menze Daniel Nguifo-Nguete Williams Tchapga Jonathan Kayondo Francis Watsenga Emile Zola Manzambi Michael Osae Charles S.Wondji 

机构地区：[1]Centre for Research in Infectious Diseases(CRID),P.O.Box 13501,Yaounde,Cameroon [2]Parasitology and Ecology Laboratory,Department of Animal Biology and Physiology,Faculty of Science,University of Yaounde 1,P.O.Box 812,Yaounde,Cameroon [3]Institut National de Recherche Biomedicale,Kinshasa,Democratic Republic of Congo [4]Radiation Entomology and Pest Management Centre,Biotechnology and Nuclear Agriculture Research Institute,Ghana Atomic Energy Commission,P.O.Box LG80,Legon-Accra,Ghana [5]Department of Vector Biology,Liverpool School of Tropical Medicine,Pembroke Place,Liverpool L35QA,UK [6]International Institute of Tropical Agriculture(IITA),P.O.Box 2008,Yaounde,Cameroon [7]Entomology Department,Uganda Virus Research Institute(UVRI),P.O.Box 49,Entebbe,Uganda.

出　　处：《Infectious Diseases of Poverty》2022年第2期23-31,共9页贫困所致传染病（英文）

基　　金：funded by the BMGF Grant(INV-006003)。

摘　　要：Background:New insecticides with a novel mode of action such as neonicotinoids have recently been recommended for public health by WHO.Resistance monitoring of such novel insecticides requires a robust protocol to monitor the development of resistance in natural populations.In this study,we comparatively used three different solvents to assess the susceptibility of malaria vectors to neonicotinoids across Africa.Methods:Mosquitoes were collected from May to July 2021 from three agricultural settings in Cameroon(Njombe-Penja,Nkolondom,and Mangoum),the Democratic Republic of Congo(Ndjili-Brasserie),Ghana(Obuasi),and Uganda(Mayuge).Using the CDC bottle test,we compared the effect of three different solvents(ethanol,acetone,MERO)on the efficacy of neonicotinoids againstAnopheles gambiae s.l.In addition,TaqMan assays were used to genotype key pyrethroid-resistant markers inAn.gambiae and odds ratio based on Fisher exact test were used to evaluate potential cross-resistance between pyrethroids and clothianidin.Results:Lower mortality was observed when using absolute ethanol or acetone alone as solvent for clothianidin(11.4-51.9% mortality in Nkolondom,31.7-48.2% in Mangoum,34.6-56.1% in Mayuge,39.4-45.6% in Obuasi,83.7-89.3% in Congo and 71.1-95.9% in Njombe pendja)compared to acetone+MERO for which 100% mortality were observed for all the populations.Similar observations were done for imidacloprid and acetamiprid.Synergist assays(PBO,DEM and DEF)with clothianidin revealed a significant increase of mortality suggesting that metabolic resistance mechanisms are contributing to the reduced susceptibility.A negative association was observed between the L1014F-kdr mutation and clothianidin resistance with a greater frequency of homozygote resistant mosquitoes among the dead than among survivors(OR=0.5;P=0.02).However,the I114T-GSTe2 was in contrast significantly associated with a greater ability to survive clothianidin with a higher frequency of homozygote resistant among survivors than other genotypes(OR=2.10;P=0.013).Conc

关 键 词：MALARIA ANOPHELES Insecticide resistance NEONICOTINOIDS CLOTHIANIDIN CROSS-RESISTANCE 

分 类 号：R184.31[医药卫生—流行病学]