Using a new odour-baited device to explore options for luring and killing outdoor-biting malaria vectors: a report on design and field evaluation of the Mosquito Landing Box

• Published in: Parasites & vectors 2013-05, Vol.6 (1), p.137-137, Article 137
• Main Authors: Matowo, Nancy S, Moore, Jason, Mapua, Salum, Madumla, Edith P, Moshi, Irene R, Kaindoa, Emanuel W, Mwangungulu, Stephen P, Kavishe, Deogratius R, Sumaye, Robert D, Lwetoijera, Dickson W, Okumu, Fredros O
• Format: Article
• Language: English
• Subjects: Adult; Animals; Anopheles; Anopheles - drug effects; Anopheles - physiology; Anopheles arabiensis; attractants; baits; Behavior, Animal - drug effects; Control; Culex; Culex - drug effects; Culex - physiology; Disease transmission; Entomology - instrumentation; Equipment and Supplies; field experimentation; Genetic vectors; host seeking; Human Experimentation; Humans; Insect Vectors - drug effects; Insect Vectors - physiology; insecticide resistance; Malaria; Male; Malvaceae - drug effects; Malvaceae - physiology; Mansonia; Methods; mortality; mosquito control; Mosquitoes; odors; people; Pesticide resistance; Pheromones - pharmacology; pirimiphos-methyl; Prevention; pyrethrins; risk; Smell - drug effects; spraying; Tanzania
• ISSN: 1756-3305; 1756-3305
• DOI: 10.1186/1756-3305-6-137

BACKGROUND: Mosquitoes that bite people outdoors can sustain malaria transmission even where effective indoor interventions such as bednets or indoor residual spraying are already widely used. Outdoor tools may therefore complement current indoor measures and improve control. We developed and evaluated a prototype mosquito control device, the ‘Mosquito Landing Box’ (MLB), which is baited with human odours and treated with mosquitocidal agents. The findings are used to explore technical options and challenges relevant to luring and killing outdoor-biting malaria vectors in endemic settings. METHODS: Field experiments were conducted in Tanzania to assess if wild host-seeking mosquitoes 1) visited the MLBs, 2) stayed long or left shortly after arrival at the device, 3) visited the devices at times when humans were also outdoors, and 4) could be killed by contaminants applied on the devices. Odours suctioned from volunteer-occupied tents were also evaluated as a potential low-cost bait, by comparing baited and unbaited MLBs. RESULTS: There were significantly more Anopheles arabiensis, An. funestus, Culex and Mansonia mosquitoes visiting baited MLB than unbaited controls (P≤0.028). Increasing sampling frequency from every 120 min to 60 and 30 min led to an increase in vector catches of up to 3.6 fold (P≤0.002), indicating that many mosquitoes visited the device but left shortly afterwards. Outdoor host-seeking activity of malaria vectors peaked between 7:30 and 10:30pm, and between 4:30 and 6:00am, matching durations when locals were also outdoors. Maximum mortality of mosquitoes visiting MLBs sprayed or painted with formulations of candidate mosquitocidal agent (pirimiphos-methyl) was 51%. Odours from volunteer occupied tents attracted significantly more mosquitoes to MLBs than controls (P