International Centre of Insect Physiology and Ecology, Nairobi, Kenya.
Parasit Vectors. 2012 May 19;5:94. doi: 10.1186/1756-3305-5-94.
Mosquitoes' response to artificial lights including color has been exploited in trap designs for improved sampling of mosquito vectors. Earlier studies suggest that mosquitoes are attracted to specific wavelengths of light and thus the need to refine techniques to increase mosquito captures following the development of super-bright light-emitting diodes (LEDs) which emit narrow wavelengths of light or very specific colors. Therefore, we investigated if LEDs can be effective substitutes for incandescent lamps used in CDC light traps for mosquito surveillance, and if so, determine the best color for attraction of important Rift Valley Fever (RFV) vectors.
The efficiency of selected colored LED CDC light traps (red, green, blue, violet, combination of blue-green-red (BGR)) to sample RVF vectors was evaluated relative to incandescent light (as control) in a CDC light trap in two RVF hotspots (Marigat and Ijara districts) in Kenya. In field experiments, traps were baited with dry ice and captures evaluated for Aedes tricholabis, Ae. mcintoshi, Ae. ochraceus, Mansonia uniformis, Mn. africana and Culex pipiens, following Latin square design with days as replicates. Daily mosquito counts per treatment were analyzed using a generalized linear model with Negative Binomial error structure and log link using R. The incidence rate ratios (IRR) that mosquito species chose other treatments instead of the control, were estimated.
Seasonal preference of Ae.mcintoshi and Ae. ochraceus at Ijara was evident with a bias towards BGR and blue traps respectively in one trapping period but this pattern waned during another period at same site with significantly low numbers recorded in all colored traps except blue relative to the control. Overall results showed that higher captures of all species were recorded in control traps compared to the other LED traps (IRR < 1) although only significantly different from red and violet.
Based on our trapping design and color, none of the LEDs outcompeted the standard incandescent light. The data however provides preliminary evidence that a preference might exist for some of these mosquito species based on observed differential attraction to these light colors requiring future studies to compare reflected versus transmitted light and the incorporation of colored light of varying intensities.
蚊子对包括颜色在内的人工灯光的反应已被应用于诱捕器设计中，以提高对蚊子媒介的采样效果。早期的研究表明，蚊子会被特定波长的光吸引，因此，随着超亮发光二极管（LED）的发展，需要改进技术以增加蚊子的捕获量，因为这些 LED 发出窄波长的光或非常特定的颜色。因此，我们研究了 LED 是否可以有效替代用于蚊虫监测的 CDC 诱捕器中的白炽灯泡，如果可以，那么确定哪种颜色最能吸引重要的裂谷热（RVF）媒介。
在肯尼亚的两个裂谷热热点（马里加特和伊贾拉地区），我们评估了选定的彩色 LED CDC 诱捕器（红色、绿色、蓝色、紫色、蓝-绿-红组合（BGR））相对于白炽灯光（对照）对 RVF 媒介的采样效率。在野外实验中，诱捕器用干冰引诱，捕获的按蚊属、曼蚊属、库蚊属、非洲曼蚊和非洲伊蚊等种类进行评估，采用拉丁方设计，以天为重复。使用 R 语言的负二项式误差结构和对数链接的广义线性模型分析每天每处理的蚊虫计数。估计了蚊虫选择其他处理而不是对照的发生率比（IRR）。
在伊贾拉，Ae. mcintoshi 和 Ae. ochraceus 的季节性偏好明显，在一个诱捕期内，它们偏向于 BGR 和蓝色诱捕器，而在同一地点的另一个诱捕期内，这种模式减弱，所有彩色诱捕器除蓝色诱捕器外记录的数量明显低于对照。总体结果表明，与其他 LED 诱捕器相比（IRR<1），所有物种在对照诱捕器中的捕获量都更高，尽管与红色和紫色诱捕器相比仅存在显著差异。
根据我们的诱捕设计和颜色，没有一种 LED 能胜过标准的白炽灯光。然而，这些数据初步表明，某些蚊子种类可能存在对这些灯光颜色的偏好，需要进一步的研究来比较反射光和透射光，以及不同强度的有色光的应用。
