DataSheet1_New self-sexing Aedes aegypti strain eliminates barriers to scalable and sustainable vector control for governments and communities in dengue-prone environments.docx

For more than 60 years, efforts to develop mating-based mosquito control technologies have largely failed to produce solutions that are both effective and scalable, keeping them out of reach of most governments and communities in disease-impacted regions globally. High pest suppression levels in trials have yet to fully translate into broad and effective Aedes aegypti control solutions. Two primary challenges to date–the need for complex sex-sorting to prevent female releases, and cumbersome processes for rearing and releasing male adult mosquitoes–present significant barriers for existing methods. As the host range of Aedes aegypti continues to advance into new geographies due to increasing globalisation and climate change, traditional chemical-based approaches are under mounting pressure from both more stringent regulatory processes and the ongoing development of insecticide resistance. It is no exaggeration to state that new tools, which are equal parts effective and scalable, are needed now more than ever. This paper describes the development and field evaluation of a new self-sexing strain of Aedes aegypti that has been designed to combine targeted vector suppression, operational simplicity, and cost-effectiveness for use in disease-prone regions. This conditional, self-limiting trait uses the sex-determination gene doublesex linked to the tetracycline-off genetic switch to cause complete female lethality in early larval development. With no female progeny survival, sex sorting is no longer required, eliminating the need for large-scale mosquito production facilities or physical sex-separation. In deployment operations, this translates to the ability to generate multiple generations of suppression for each mosquito released, while being entirely self-limiting. To evaluate these potential benefits, a field trial was carried out in densely-populated urban, dengue-prone neighbourhoods in Brazil, wherein the strain was able to suppress wild mosquito populations by up to 96%, demonstrating the utility of this self-sexing approach for biological vector control. In doing so, it has shown that such strains offer the critical components necessary to make these tools highly accessible, and thus they harbour the potential to transition mating-based approaches to effective and sustainable vector control tools that are within reach of governments and at-risk communities who may have only limited resources.

六十余年来，全球范围内针对基于交配的蚊虫防控技术的研发尝试，大多未能产出兼具有效性与可扩展性的成熟方案，致使全球多数受疾病影响地区的政府与社区始终难以获取此类技术。试验中实现的高蚊虫种群抑制率，尚未完全转化为可广泛应用的高效埃及伊蚊（Aedes aegypti）防控方案。迄今为止，两大核心瓶颈始终制约着现有技术的发展：一是需要通过复杂的性别分选流程避免释放雌蚊，二是成年雄蚊的饲养与释放流程繁琐冗杂，二者均构成了显著的应用壁垒。随着全球化进程加速与气候变化加剧，埃及伊蚊的分布范围持续向新的地理区域扩张，传统化学防控手段正面临愈发严格的监管审批要求，以及蚊虫杀虫剂抗性不断演化带来的双重压力。可以毫不夸张地说，当下比以往任何时候都更需要兼具有效性与可扩展性的新型防控工具。本论文阐述了一种新型埃及伊蚊自性别品系（self-sexing strain）的研发与田间评估工作，该品系专为疾病高发区域设计，可实现靶向媒介抑制、操作简便性与成本效益的有机统一。该条件性自限性状依托与四环素关闭（tetracycline-off）遗传开关相连的性别决定基因doublesex，可在幼虫早期发育阶段诱导雌蚊完全致死。由于无雌性后代存活，无需再进行性别分选，彻底免除了大规模蚊虫生产设施或物理性别分离流程的需求。在实际部署应用中，这一特性意味着每释放一只蚊虫即可产生多代种群抑制效果，且全程完全自限。为评估这些潜在优势，研究团队在巴西登革热高发的高密度城市社区开展了田间试验，结果显示该品系可将野生蚊虫种群抑制率最高达96%，证实了此种自性别策略在生物媒介防控中的应用价值。此项研究表明，此类品系具备使这类防控工具实现高可及性所需的关键特性，因此有望推动基于交配的防控方法转型为高效且可持续的媒介防控手段，让资源有限的政府与高风险社区也能获取此类技术。