Mosquito-Borne Diseases: A Q&A With Leading Global Experts

Moderated by Frederic Schmitt, Ph.D., Envu senior global project leader, this live panel discussion brought together Corine Ngufor, Ph.D., of the London School of Hygiene & Tropical Medicine; Professor Fredros Okumu, Ph.D., from the University of Glasgow; and Christen Fornadel, Ph.D., of the Innovative Vector Control Consortium (IVCC). Together, they discussed how integrated strategies can significantly enhance vector control efforts and why a multilayered approach to tackling mosquito-borne diseases is more crucial than ever before.

Four Key Takeaways:

1. Integrated, Layered Approaches for Effective Vector Control: Combining multiple tools — like insecticide-treated nets, indoor residual spraying and larval source management — enhances mosquito control by creating layered protection tailored to local contexts. This approach maximizes resources and effectiveness by reducing the "gaps" in protection.
2. Data-Driven, Locally Adapted Strategies: Successful vector control relies on data interpretation within local contexts. By partnering with universities and experts, countries can create more effective and sustainable interventions that align with specific community needs.
3. The Role of Economic Development in Long-Term Solutions: Addressing root causes of mosquito-borne diseases involves economic improvements — like better housing and sanitation — which reduce disease transmission over time. Innovations must be complemented by strategies that help break the poverty disease cycle.
4. Emerging Innovations and Long-Term Investments: Tools like gene drive mosquitoes and sterile insect technique represent transformative potential for mosquito control. These technologies, combined with stable investments, could offer long-term solutions to the growing threat of vector-borne diseases.

Below, you will find the full panel discussion recording and the top questions and answers from the insightful live discussion.

What is integrated vector management (IVM) and why is it essential?

Corine Ngufor: Integrated vector management is about creating an adaptable, data-driven approach for controlling multiple vector-borne diseases — like malaria, dengue and Zika — efficiently and sustainably. It’s about applying the right tools in the right places, targeting multiple vectors to optimize resources. The World Health Organization (WHO) has defined it as a decision-making process where we adapt our interventions based on local needs and scale the most effective measures to achieve the greatest impact. This approach includes enhanced vector surveillance and community engagement, ensuring an intersectoral collaboration where governments, communities and experts come together to reduce disease burdens.

How do you combine various tools within IVM for maximum impact?

Christen Fornadel: I often think of each prevention tool as a slice of Swiss cheese with holes mosquitoes might slip through. When we layer these slices, or tools, together, the holes diminish, creating a solid layer of protection. The tools we rely on include insecticide-treated nets (ITNs), indoor residual spraying (IRS) and larval source management, among others. Selecting the right combination of these tools depends heavily on the local context. For instance, in areas where people don’t use bed nets due to cultural preferences or climate, it may be better to emphasize IRS combined with other options. It’s about using data to understand local needs and carefully stacking prevention tools for the most effective outcome.

Fredros Okumu: I’d add that the effectiveness of IVM also depends on using data to select interventions with the highest impact, given our limited resources. It’s about balancing efficacy with sustainability. In cases where funding is tight, focusing on the interventions that will yield the highest value is essential. For example, rather than applying a broad spectrum of tools, countries may achieve better results by concentrating resources on a select few and executing those exceptionally well.

How should countries handle data to make effective, locally tailored decisions?

Fredros Okumu: Data-driven decision-making requires not only collecting and analyzing data but also interpreting it effectively within the local context. Many endemic countries have made strides in this area, though some gaps remain. While many programs can handle basic data analysis, building capacity for interpreting and translating data into actionable strategies is where there’s room for growth. Additionally, countries should aim to foster partnerships with universities or research centers. Leveraging in-country expertise helps national programs optimize their strategies without always requiring an extensive internal team.

Christen Fornadel: Data interpretation is indeed critical, especially as countries tailor interventions to fit unique conditions on the ground. Even advanced models don’t account for all local nuances, like how a particular community might use bed nets for fishing instead of protection. So, an iterative process is essential — where program managers, researchers and funders work together, continuously refining interventions based on both data insights and realities in the field.

Given limited resources, what strategies can maximize the impact of vector control efforts?

Corine Ngufor: When resources are limited, targeting highly affected areas and strategically layering interventions is crucial. Rather than blanket solutions, focusing efforts where the impact will be greatest makes a significant difference. Tailored approaches are also important. For instance, deploying IRS in high-transmission areas while relying on other interventions like larval source management in regions where mosquitoes are more active outdoors.

Fredros Okumu: The WHO’s Global Vector Response emphasizes multisectoral partnerships. National programs don’t always need to possess every skill internally; instead, they can rely on local universities or experts for specific needs, like data modeling. For example, in Tanzania, we partner with the National Malaria Control Program to provide support that complements their capabilities. Such collaborations allow us to tackle challenges more comprehensively while effectively managing resources.

What interventions are most critical in curbing disease spread given the convergence of multiple species and diseases?

Fredros Okumu: The fundamental challenge isn’t so much about scientific breakthroughs — we’ve known how to control mosquitoes for over a century. It's about financing and sustained commitment. Transformative tools like gene drive mosquitoes could change the game, but otherwise, we're often in a “rat race” with year-over-year interventions like IRS and bed nets. For lasting impact, countries need to focus on building “'structural resilience,” like improved housing and education and reduced poverty to sustain gains when these interventions wane.

Corine Ngufor: I agree entirely. The root cause of malaria is tied closely to poverty. As people gain access to better housing and a clean environment, malaria rates decline significantly. But innovation remains crucial. Mosquitoes adapt to our methods — pyrethroid resistance and outdoor biting, for instance, are new challenges we didn’t anticipate. Staying ahead means constantly innovating and adapting our strategies.

Christen Fornadel: I also agree that economic development is key to ending malaria, but there's a cyclical issue where malaria perpetuates poverty by preventing people from working and children from attending school. Innovations like spatial emanators, which protect the entire household from bites, offer a way to tackle both indoor and outdoor transmission, potentially helping us break this malaria poverty cycle.

How can resource-limited countries be motivated to adopt and fund effective solutions?

Fredros Okumu: It’s all about prioritization and leadership. Even with limited resources, countries can achieve reductions by making minor housing improvements and maintaining good access to health care, as seen in towns like Ifakara in Tanzania. But viewing malaria control as a generational problem, with sustainable funding models and long-term strategies, is essential to lasting progress.

Christen Fornadel: In the short term, we should collaborate with private sector industries like mining and agriculture, which already conduct vector control to protect their workers. These sectors could play a bigger role in supporting local malaria control efforts, filling gaps until countries build longer-term investments.

Corine Ngufor: We also need a multisector approach, where agriculture and education, for instance, contribute to the malaria fight, not just health ministries. Additionally, localizing production of interventions could improve acceptance and use as communities take ownership of tools they produce locally for their benefit.

The panel emphasized that while financing and new technology play vital roles in controlling vector-borne diseases, the ultimate solution lies in long-term economic development and strategic, cross-sector collaboration.

Can spatial repellents be used alone, and how does this impact budget considerations?

Christen Fornadel: Current trials add spatial repellents on top of universal bed net coverage, but budget constraints make this unrealistic. Spatial repellents and bed nets both inhibit bites, so layering them might be redundant. We should consider trials for spatial repellents on their own to see if they could be recommended without the additional cost of bed nets.

Corine Ngufor: While spatial repellents show promise, I wouldn’t support removing nets without evidence. However, spatial repellents could address gaps when nets are less effective, such as after three years when coverage declines.

Should we expand our malaria control approaches to include interventions like environmental management and town planning?

Corine Ngufor: Yes, IVM should centralize interventions like sanitation and environmental management alongside vector-targeting strategies. Governments should prioritize these measures for broader public health benefits.

How can Ministries of Health advocate effectively when global funders resist their approaches?

Christen Fornadel: It requires strong country leadership and iterative dialogue. Ghana, for instance, advocated for its IRS program, unlike other countries where funding was cut. Strong ownership and pushing for data-driven solutions are essential.

What role do technologies like sterile insect technique (SIT) and genetically modified mosquitoes play in future strategies?

Fredros Okumu: SIT is transformative for specific arthropods and could address challenges like increasing dengue prevalence due to climate change.

Are there solutions to reduce outdoor mosquito biting?

Corine Ngufor: Outdoor biting remains a challenge. There’s potential in outdoor spraying and larviciding, but we need more research on effective outdoor interventions and their actual impact on malaria transmission.

Christen Fornadel: Outdoor exposure is one part of residual transmission; we need to address mosquito exposure both indoors and outdoors. Innovative approaches like attractive targeted sugar baits may target mosquitoes at different life stages, but further innovation is needed.

The panel underscored that while current tools and innovations like spatial repellents and gene drive mosquitoes offer promising avenues, the long-term fight against mosquito-borne diseases demands a multilayered approach grounded in local context, data-driven adaptation and reliable financing. They highlighted that resource-limited regions can make significant strides by prioritizing key interventions, collaborating with sectors beyond public health and fostering community engagement.

Ultimately, Okumu, Ngufor and Fornadel emphasized that true, lasting progress relies not only on continuous innovation in mosquito control but on building economic resilience and structural improvements, such as better housing and education, to prevent transmission. Looking ahead, strategic investments in both transformative technologies and cross-sector partnerships will be essential to reducing the global threat of mosquito-borne diseases.

To take action, Envu works alongside leading institutions and organizations around the world to develop economically and environmentally sustainable approaches that reduce the impact of mosquitoes on public health. By preventing the threat of mosquitoes today, we help communities thrive tomorrow. Because to be a positive force for human health, we must be a force with nature.

Learn more about Envu Mosquito Management.