| Title: | Combining Synthetic Human Odours and Low-Cost Electrocuting Grids to Attract and Kill Outdoor-Biting Mosquitoes: Field and Semi-Field Evaluation of an Improved Mosquito Landing Box |
| Author(s): | Matowo NS; Koekemoer LL; Moore SJ; Mmbando AS; Mapua SA; Coetzee M; Okumu FO; |
| Address: | "Environmental and Ecological Sciences Thematic Group, Ifakara Health Institute, Dar es Salaam, Tanzania. Wits Research Institute for Malaria, School of Pathology, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa. Centre for Opportunistic, Tropical and Hospital Infections, National Institute for Communicable Diseases, Johannesburg, South Africa. Swiss Tropical and Public Health Institute, Basel, Switzerland. University of Basel, Basel, Switzerland. School of Public Health, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa" |
| DOI: | 10.1371/journal.pone.0145653 |
| ISSN/ISBN: | 1932-6203 (Electronic) 1932-6203 (Linking) |
| Abstract: | "BACKGROUND: On-going malaria transmission is increasingly mediated by outdoor-biting vectors, especially where indoor insecticidal interventions such as long-lasting insecticide treated nets (LLINs) are widespread. Often, the vectors are also physiologically resistant to insecticides, presenting major obstacles for elimination. We tested a combination of electrocuting grids with synthetic odours as an alternative killing mechanism against outdoor-biting mosquitoes. METHODS: An odour-baited device, the Mosquito Landing Box (MLB), was improved by fitting it with low-cost electrocuting grids to instantly kill mosquitoes attracted to the odour lure, and automated photo switch to activate attractant-dispensing and mosquito-killing systems between dusk and dawn. MLBs fitted with one, two or three electrocuting grids were compared outdoors in a malaria endemic village in Tanzania, where vectors had lost susceptibility to pyrethroids. MLBs with three grids were also tested in a large semi-field cage (9.6 x 9.6 x 4.5m), to assess effects on biting-densities of laboratory-reared Anopheles arabiensis on volunteers sitting near MLBs. RESULTS: Significantly more mosquitoes were killed when MLBs had two or three grids, than one grid in wet and dry seasons (P<0.05). The MLBs were highly efficient against Mansonia species and malaria vector, An. arabiensis. Of all mosquitoes, 99% were non-blood fed, suggesting host-seeking status. In the semi-field, the MLBs reduced mean number of malaria mosquitoes attempting to bite humans fourfold. CONCLUSION: The improved odour-baited MLBs effectively kill outdoor-biting malaria vector mosquitoes that are behaviourally and physiologically resistant to insecticidal interventions e.g. LLINs. The MLBs reduce human-biting vector densities even when used close to humans, and are insecticide-free, hence potentially antiresistance. The devices could either be used as surveillance tools or complementary mosquito control interventions to accelerate malaria elimination where outdoor transmission is significant" |
| Keywords: | Animals Culicidae/classification/*physiology Female Humans Insect Bites and Stings/*prevention & control Insecticide-Treated Bednets Malaria/*prevention & control Male Mosquito Control/economics/*instrumentation/methods Odorants Pheromones/economics/*ther; |
| Notes: | "MedlineMatowo, Nancy S Koekemoer, Lizette L Moore, Sarah J Mmbando, Arnold S Mapua, Salum A Coetzee, Maureen Okumu, Fredros O eng WT_/Wellcome Trust/United Kingdom Comparative Study Research Support, Non-U.S. Gov't 2016/01/21 PLoS One. 2016 Jan 20; 11(1):e0145653. doi: 10.1371/journal.pone.0145653. eCollection 2016" |
