The Center for Evolution & Medicine, School of Life Sciences, Arizona State University, Tempe, Arizona, United States America.
Simon A. Levin Mathematical, Computational and Modeling Sciences Center, Arizona State University, Tempe, Arizona, United States America.
PLoS Negl Trop Dis. 2024 Sep 13;18(9):e0012493. doi: 10.1371/journal.pntd.0012493. eCollection 2024 Sep.
The control and prevention of mosquito-borne diseases is mostly achieved with insecticides. However, their use has led to the rapid development and spread of insecticide resistance worldwide. Health experts have called for intensified efforts to find new approaches to reduce mosquito populations and human-mosquito contact. A promising new tool is the use of electrical fields (EFs), whereby mosquitoes are repelled by charged particles in their flight path. Such particles move between two or more conductors, and the use of uninsulated copper or aluminum plates as conductors has been proven to be effective at repelling mosquitoes. Here, for the first time, we assess if EFs generated using a single row of insulated conductor wires (ICWs) can also successfully repel mosquitoes, and whether mosquitoes are equally repelled at the same EF strength when the electrodes are a) orientated differently (horizontal vs. vertical placement), and b) spaced more apart.
METHODOLOGY/PRINCIPAL FINDINGS: Over a period of 23 hours, the number of host-seeking female Aedes aegypti mosquitoes that were successfully repelled by EFs, using ICWs, at EF strengths ranging from 0 kV/cm (control) to 9.15 kV/cm were quantified. Mosquitoes were released inside a 220×220×180 cm room and lured into a BG-Pro trap that was equipped with a BG-counter and baited with CO2 using dry ice. Mosquitoes had to pass through an EF window, that contained a single row of ICWs with alternating polarity, to reach the bait. The baseline interaction between EF strength and repellency was assessed first, after which the impact of different ICW orientations and ICW distances on repellency were determined. Over 50% of mosquitoes were repelled at EF strengths of ≥ 3.66 kV/cm. A linear regression model showed that a vertical ICW orientation (vertical vs. horizontal) had a small but insignificant increased impact on mosquito repellency (p = 0.059), and increasing ICW distance (while maintaining the same EF strength) significantly reduced repellency (p = 0.01).
CONCLUSIONS/SIGNIFICANCE: ICWs can be used to generate EFs that partially repel host-seeking mosquitoes, which will reduce human-mosquito contact. While future studies need to assess if (i) increased repellency can be achieved, and (ii) a repellency of 50-60% is sufficient to impact disease transmission, it is encouraging that EF repellency using ICWs is higher compared to that of some spatial repellent technologies currently in development. This technology can be used in the housing improvement toolkit (i.e. preventing mosquito entry through eaves, windows, and doors). Moreover, the use of cheap, over-the-counter ICWs will mean that the technology is more accessible worldwide, and easier to manufacture and implement locally.
蚊虫传染病的控制和预防主要通过杀虫剂来实现。然而，杀虫剂的使用导致了全球范围内昆虫抗药性的迅速发展和传播。健康专家呼吁加紧努力，寻找新的方法来减少蚊子数量和减少人与蚊子的接触。一种有前途的新工具是利用电场（EFs），通过在蚊子的飞行路径中排斥带电荷的粒子来达到驱赶蚊子的效果。这些带点粒子在两个或更多导体之间移动，使用未绝缘的铜或铝板作为导体已被证明可以有效驱赶蚊子。在这里，我们首次评估使用单排绝缘导体线（ICWs）产生的 EF 是否也可以成功驱赶蚊子，以及当电极 a）以不同的方向（水平与垂直放置）和 b）间隔更大时，蚊子在相同的 EF 强度下是否同样被驱赶。
方法/主要发现：在 23 小时的时间内，使用 ICWs 以 0 kV/cm（对照）至 9.15 kV/cm 的 EF 强度量化了成功被驱赶的雌性埃及伊蚊数量。蚊子在一个 220×220×180 cm 的房间内被释放，并被引诱到配备 BG-counter 的 BG-Pro 陷阱中，该陷阱用干冰引诱 CO2 作为诱饵。蚊子必须穿过一个包含单排交替极性的 ICWs 的 EF 窗口才能到达诱饵。首先评估 EF 强度和驱避率之间的基本相互作用，然后确定不同的 ICW 方向和 ICW 距离对驱避率的影响。超过 50%的蚊子在 EF 强度≥3.66 kV/cm 时被驱赶。线性回归模型显示，垂直 ICW 方向（垂直与水平）对蚊子驱避率有较小但无统计学意义的影响（p = 0.059），而增加 ICW 距离（同时保持相同的 EF 强度）显著降低了驱避率（p = 0.01）。
结论/意义：ICWs 可用于产生部分驱赶寻找宿主的蚊子的 EF，从而减少人与蚊子的接触。虽然未来的研究需要评估（i）是否可以提高驱避率，以及（ii）是否达到 50-60%的驱避率足以影响疾病传播，但令人鼓舞的是，使用 ICWs 的 EF 驱避率高于目前正在开发的一些空间驱避技术。该技术可用于住房改善工具包（即通过屋檐、窗户和门防止蚊子进入）。此外，使用廉价的现成 ICWs 将意味着该技术在全球范围内更容易获得，并且更容易在当地制造和实施。
