Delftia tsuruhatensis TC1 based-intervention for interrupting malaria transmission in mosquitoes

A New Way to Fight Malaria without harming the mosquito

Malaria is one of the world’s deadliest diseases, affecting over 200 million people every year and causing more than 600,000 deaths, mostly in young children and remains a huge challenge, especially in Sub Saharan Africa. It spreads through mosquito bites, and while current tools like insecticides have helped reduce malaria in many areas, the fight against the disease is becoming harder. Widespread use of insecticide-based malaria control tools indoor residual sprays (IRS) or insecticide-Treated Nets (ITNs), have led to a rapid emergence of mosquito resistance making them less effective over time. To tackle this challenge, our team has developed an exciting new approach to fight malaria using a bacteria called Delftia tsuruhatensis TC1 (or simply TC1). TC1 produces a natural substance called Harmane, which stops the malaria parasite from growing inside mosquitoes. This means the mosquitoes can no longer carry the parasite and transmit the disease to humans. What’s unique about TC1 is that it doesn't kill or harm mosquitoes and hence they do not develop resistance like they do with chemical insecticides. This makes TC1 a powerful and sustainable solution for malaria control. We've conducted extensive studies in laboratories and semi-field environments to make sure TC1 is safe, effective, and can be produced in large amounts.

The results have been very promising, and now via this EDCTP3-funded DEFEND project we are preparing to test it in real-world settings in Burkina Faso and Senegal, two countries where malaria is a major problem.

Our approach

Testing TC1 in communities requires a new approach. Most insecticide-based vector control tools kill mosquitoes and are evaluated through large, expensive trials that measure how they impact entire populations. However, TC1 works differently—it blocks malaria at the stage where the parasite is developing inside the mosquito without killing it. For these types of non-insecticide-based tools we need to devise novel type of trials to demonstrate effectiveness. In the DEFEND project we are working on a new way to test how well TC1 works in real-world outdoor conditions in Burkina Faso and Senegal. We will deploy TC1 via sugar baits in various houses within communities and estimate reduction of malaria burden within an individual mosquito. The goal of this novel trial is to demonstrate the effectiveness within these communities and use this data in modelling studies to predict the public health impact of TC1 on malaria transmission.

Why DEFEND matters

This project is essential not only for malaria but also for other diseases spread by insects, like leishmaniasis and dengue. By creating new ways to test tools like TC1, we can speed up the process of getting them approved and deployed to the people who need them most. Malaria has been a global health challenge for generations, but with innovative solutions like TC1, there is real hope for eradicating this disease. With results from our DEFEND project, we hope that this new tool will be used by national malaria control programs and organizations alongside existing strategies to eliminate malaria. If successful, it could potentially help protect millions of lives and pave the way for safer, smarter tools to combat other vector-borne diseases in the future.