Insecticide resistance mechanisms associated with different environments in the malaria vector Anopheles gambiae: a case study in Tanzania

Malaria Journal

Research

Franklin Mosha¹  Idir Akhouayri²  Jean-Philippe David²  Theresia E Nkya³  Rodolphe Poupardin⁴  Bernard Batengana⁵  William Kisinza⁵  Stephen Magesa⁶ 

[1] KCM College of Tumaini University, P. O. Box. 2240, Moshi, Tanzania;Laboratoire d'Ecologie Alpine, UMR CNRS-Université de Grenoble 5553, BP 53, 38041, Grenoble cedex 09, France;Laboratoire d'Ecologie Alpine, UMR CNRS-Université de Grenoble 5553, BP 53, 38041, Grenoble cedex 09, France;National Institute of Medical Research of Tanzania, Amani Medical Research Centre, P. O. Box 81, Tanga, Muheza, Tanzania;Liverpool School of Tropical Medicine, Vector Group, Pembroke place, L35QA, Liverpool, UK;National Institute of Medical Research of Tanzania, Amani Medical Research Centre, P. O. Box 81, Tanga, Muheza, Tanzania;RTI International-Tanzania, P.O.Box 369, Dar es Salaam, Tanzania;

关键词: Malaria vector;    Mosquitoes;    Anopheles;    Insecticide resistance;    Agriculture;    Pollution;    Detoxification enzymes;    Kdr mutation;    Environment;   

DOI  :  10.1186/1475-2875-13-28

 received in 2013-10-09, accepted in 2014-01-21,  发布年份 2014

来源: Springer

【 摘 要 】

BackgroundResistance of mosquitoes to insecticides is a growing concern in Africa. Since only a few insecticides are used for public health and limited development of new molecules is expected in the next decade, maintaining the efficacy of control programmes mostly relies on resistance management strategies. Developing such strategies requires a deep understanding of factors influencing resistance together with characterizing the mechanisms involved. Among factors likely to influence insecticide resistance in mosquitoes, agriculture and urbanization have been implicated but rarely studied in detail. The present study aimed at comparing insecticide resistance levels and associated mechanisms across multiple Anopheles gambiae sensu lato populations from different environments.MethodsNine populations were sampled in three areas of Tanzania showing contrasting agriculture activity, urbanization and usage of insecticides for vector control. Insecticide resistance levels were measured in larvae and adults through bioassays with deltamethrin, DDT and bendiocarb. The distribution of An. gambiae sub-species and pyrethroid target-site mutations (kdr) were investigated using molecular assays. A microarray approach was used for identifying transcription level variations associated to different environments and insecticide resistance.ResultsElevated resistance levels to deltamethrin and DDT were identified in agriculture and urban areas as compared to the susceptible strain Kisumu. A significant correlation was found between adult deltamethrin resistance and agriculture activity. The subspecies Anopheles arabiensis was predominant with only few An. gambiae sensu stricto identified in the urban area of Dar es Salaam. The L1014S kdr mutation was detected at elevated frequency in An gambiae s.s. in the urban area but remains sporadic in An. arabiensis specimens. Microarrays identified 416 transcripts differentially expressed in any area versus the susceptible reference strain and supported the impact of agriculture on resistance mechanisms with multiple genes encoding pesticide targets, detoxification enzymes and proteins linked to neurotransmitter activity affected. In contrast, resistance mechanisms found in the urban area appeared more specific and more related to the use of insecticides for vector control.ConclusionsOverall, this study confirmed the role of the environment in shaping insecticide resistance in mosquitoes with a major impact of agriculture activities. Results are discussed in relation to resistance mechanisms and the optimization of resistance management strategies.

【 授权许可】

Unknown   
© Nkya et al.; licensee BioMed Central Ltd. 2014. This article is published under license to BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.