12Sep 24
World Mosquito Day offers an opportunity to raise awareness of the challenges posed by mosquito-borne diseases worldwide and highlight ongoing efforts to address this threat. Almost 700 million people contract a mosquito-borne disease every year.
Aedes mosquitoes are one of the main disease-spreading mosquitoes, annually impacting millions across the globe through diseases like dengue, yellow fever, chikungunya and Zika. Warmer temperatures and higher levels of precipitation and humidity are expanding the habitat of Aedes mosquitoes, allowing them to thrive in regions previously unsuitable for their survival. Compounding this issue, the mosquito’s growing resistance to insecticides is weakening one of the primary defenses against this disease vector.
Dengue, a viral infection transmitted primarily through the bite of infected Aedes aegypti mosquitoes, stands out as a rapidly growing concern. As of July this year, over 10 million cases of dengue had been reported from 176 countries, making 2024 the worst year for cases on record of the disease. The resurgence and geographical spread of dengue have been facilitated by urbanization, the movement of people and goods, and shifting weather patterns due to climate change. Many regions in different parts of the world are experiencing unprecedented outbreaks; this increase has been particularly pronounced in the Region of the Americas, with Brazil accounting for a majority of cases.
The global spread of Aedes mosquitoes underscores the urgent need for concerted efforts and a multipronged approach to control and eliminate the diseases they transmit. In response to evolving threats, researchers are exploring new strategies to fight these mosquitoes, such as gene drive technologies. In this piece, 6 researchers tell us about their work to develop innovative tools to control Aedes mosquitoes and help combat the spread of the diseases they carry.
Eunice Oluwatobiloba Adedeji, Postdoctoral Research Associate, Alphey Lab, University of York
With Aedes aegypti mosquitoes becoming more resistant to insecticides, it is critical to develop new strategies to limit the spread of the diseases they transmit. The possibility of genetically modifying mosquitoes either to suppress mosquito populations or to make them unable to transmit disease-causing parasites offers advantages over conventional control methods. The use of self-sustaining gene drive could help minimize the need for continuous interventions, making control efforts more affordable and effective. In our laboratory at the University of York, we use CRISPR/Cas9 technology to modify the biology of Aedes aegypti. We combine and optimize different genetic elements, generating genetic control systems to modify this mosquito species with the aim of reducing the population of mosquitoes. This approach could be of great benefit, as Aedes aegypti mosquitoes have a wide geographical spread and are a vector of many diseases.
Jialiang Guo, Graduate Student, Champer Lab, Universidad de Pekín
In recent years, CRISPR-based gene drives have gained traction as a tool that allows to efficiently spread specific traits within target populations, by biasing their inheritance. This has created exciting opportunities for mosquito control, enabling us to develop new tools that could reduce disease transmission. I am currently working on modeling the spread of self-limiting drive systems that impose a temporal restriction on the persistence of a modification. Modeling could help us predict the performance of a gene drive system in wild populations, marking a step towards potential future field releases. Going forward, I plan to work on developing a confined drive system in Aedes aegypti mosquitoes, which are known vectors of several diseases, including dengue, chikungunya, yellow fever, and Zika.
Jie Du, Postdoctoral Researcher, Champer Lab, Universidad de Pekín
Aedes aegypti mosquitoes spread dengue, Zika virus, and other diseases. They are becoming an even greater threat due to the effects of climate change. As global temperatures rise and weather patterns shift, these mosquitoes are expanding their range, increasing the risk of disease outbreaks in new regions. My work is focused on researching the use of gene drive technologies in these mosquitoes. Part of our work consists of exploring strategies that could help overcome potential resistance to gene drive systems. We hope to develop a successful gene drive approach that can spread effectively and safely through a population of Aedes aegypti mosquitoes and could be used in the future to reduce disease transmission.
Shih-Che Weng, Postdoctoral Scholar, The Akbari Lab, University of California San Diego (UCSD)
Mosquito-borne diseases like malaria, filariasis, dengue, and Zika cause over one million deaths annually and pose a significant threat to humans and animals. This underscores the importance of a One Health approach that integrates human, animal, and environmental health. Climate change and increased travel expand mosquito habitats, further intensifying these challenges. My academic journey began at National Taiwan University, where I studied the relationship between reproductive regulation and virus replication in Aedes aegypti mosquitoes. My current research at UC San Diego centers on mosquito sex determination and differentiation, with a focus on the role of female mosquitoes in disease transmission. I developed SEPARATOR, a sex-sorting approach, to improve mosquito population control through precise male mosquito selection and release. Through this research, I hope to contribute to a healthier and safer world.
Victoria Hill, Postdoctoral Research Associate, Alphey Lab, University of York
Despite having a relatively low number of chromosomes, the Aedes aegypti genome is almost 5-fold larger than that of the malaria vector Anopheles gambiae.This complexity makes identifying genes, especially their regulatory regions, more challenging, as they may be spread out over longer segments of DNA. My research focuses on developing techniques called immunofluorescence (IF) and fluorescent in-situ hybridization (FISH) to more reliably determine transgene expression patterns. This can guide improvements in genetic modifications to favor inheritance of desirable traits. With Aedes aegypti geographically expanding due to insecticide resistance and climate change, it is important that alternative strategies are considered to manage this mosquito species. Ultimately, the goal of modifying these mosquitoes is to develop a sustainable new tool to control Aedes aegypti mosquitoes and reduce disease transmission.
Weizhe Chen, Graduate Student, Champer Lab, Universidad de Pekín
Aedes aegypti mosquitoes are known vectors of several diseases, including dengue, chikungunya, yellow fever, and Zika, which impact millions of people worldwide each year. I am a second-year PhD
student focusing on developing advanced multiplexed guide RNA-based gene drives. I am currently working to design an efficient gene drive system in Aedes aegypti mosquitoes. If successful, this approach could be used as an additional tool to help control these mosquitoes and reduce the transmission of diseases such as dengue.
