The contribution of aestivating mosquitoes to the persistence of Anopheles gambiae in the Sahel

Malaria Journal

Research

Tovi Lehmann¹  Diana L Huestis¹  Alpha Seydou Yaro²  Adama Dao²  Moussa Diallo²  Abdoulaye Adamou²  Yaya Kassogué²  Sékou F Traoré²  Seydou Timbine² 

[1] Laboratory of Malaria and Vector Research, NIAID, NIH, Rockville, MD, USA;Malaria Research and Training Center (MRTC)/Faculty of Medicine, Pharmacy and Odontostomatology, Bamako, Mali;

关键词: Malaria;    Malaria Transmission;    Molecular Form;    Mosquito Density;    Anopheles Arabiensis;   

DOI  :  10.1186/1475-2875-10-151

 received in 2011-03-13, accepted in 2011-06-06,  发布年份 2011

来源: Springer

【 摘 要 】

BackgroundPersistence of African anophelines throughout the long dry season (4-8 months) when no surface waters are available remains one of the enduring mysteries of medical entomology. Recent studies demonstrated that aestivation (summer diapause) is one mechanism that allows the African malaria mosquito, Anopheles gambiae, to persist in the Sahel. However, migration from distant localities - where reproduction continues year-round - might also be involved.MethodsTo assess the contribution of aestivating adults to the buildup of populations in the subsequent wet season, two villages subjected to weekly pyrethrum sprays throughout the dry season were compared with two nearby villages, which were only monitored. If aestivating adults are the main source of the subsequent wet-season population, then the subsequent wet-season density in the treated villages will be lower than in the control villages. Moreover, since virtually only M-form An. gambiae are found during the dry season, the reduction should be specific to the M form, whereas no such difference is predicted for S-form An. gambiae or Anopheles arabiensis. On the other hand, if migrants arriving with the first rain are the main source, no differences between treated and control villages are expected across all members of the An. gambiae complex.ResultsThe wet-season density of the M form in treated villages was 30% lower than that in the control (P < 10-4, permutation test), whereas no significant differences were detected in the S form or An. arabiensis.ConclusionsThese results support the hypothesis that the M form persist in the arid Sahel primarily by aestivation, whereas the S form and An. arabiensis rely on migration from distant locations. Implications for malaria control are discussed.

【 授权许可】

Unknown   
© Abdoulaye et al; licensee BioMed Central Ltd. 2011. 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.