Current strategies to prevent malaria using bed nets and insecticides protect millions of people from malaria-transmitting mosquitoes. Last year 175 million bed nets treated with insecticide were delivered across sub-Saharan Africa. Between 2000 and 2015 bed nets are estimated to have prevented an estimated
But these measures offer only limited protection. According to the latest World Malaria Report, 44% of people in African countries with high malaria rates don’t have access to bed nets and insecticides. Even when they are available, they’re not failsafe. For example, the use of bed nets has been linked to an increase in mosquitoes biting outdoors, and they can also develop resistance to the insecticide.
Worldwide there were 435,000 deaths last year from malaria. Over 90% were in Africa. This means that scientists need to redouble efforts to develop new, complementary measures to eliminate the disease.
One promising solution includes reducing the population of malaria mosquitoes through genetic modification to help reach the target of ending transmission.
Target Malaria, a research consortium working across the USA, Europe and Africa, is in the early stages of developing a genetically modified mosquito that can either produce only male offspring or reduce female fertility in subsequent generations.
Where I work in Mali, we are currently studying local mosquito populations to help inform work on genetic modification.
Though the scientific research often gets the limelight, the process also involves working side by side with local communities from the very beginning. This engagement helps us get not only the communities’ feedback but also their active participation.
Our work in Mali involves trying to understand the mosquito species that are responsible for malaria transmission and to gather as much baseline data as possible on the local malaria mosquitoes. These data include: abundance, biting and resting behaviour, migration, effective population size. This is a crucial first step that will be the basis for further work in our country.
Genetic modification could be achieved in one of two ways.
The first is to bias the sex ratio so future offspring would be all males. This is done by fragmenting the X chromosome in the males so they only pass on a Y chromosome. As a result, their offspring is male (XY), as a female would need to inherit an X from each parent (XX).
The second way is to reduce female fertility. This is achieved by targeting the gene responsible for fertility in females. A female that has one copy of this fertility gene disrupted will be able to reproduce normally, but when both copies within her chromosomes are disrupted, the female cannot produce viable offspring, reducing the mosquito population.
But as the science to make this possible gets closer, we must ensure that the public debate around such a novel and potentially transformative technology also keeps up.
This means not only exploring what we can do in a laboratory, but exploring and understanding what is acceptable to the communities most affected by such innovations. We need to ensure that any new malaria control method fully meets their needs.
In Mali, where Target Malaria has been working since 2012, there is an ongoing dialogue at national, regional and community levels.
Our teams visit the communities around our in-sectary where insects are kept and studied, as well as field sites nearly every week and community members visit our laboratories. We also get permission from individual households to collect mosquitoes from homes or compounds. And we ask communities before we catch mosquitoes in swarms.
But engagement is not just about information and acceptance, it’s also about collaboration. Our “relay” staff, who live in the communities, can provide information even when we are not there.
On top of this we respect the decision-making processes of each individual village regardless of how different the processes can be.
We will continue following this way of doing things for each subsequent phase of our work.
The reason for such extensive and transparent engagement is clear.
As researchers, our role is not only to determine whether the genetic alteration of mosquitoes to stop malaria is scientifically possible. It is also to ensure that this can be done ethically and responsibly to meet the needs of the affected population. We can only do this by involving them.
Mamadou Coulibay, Head, Malaria Research and Training Center, Université des sciences, des techniques et des technologies de Bamako