This could very well be the last century in human history when people die from malaria. If and when we do eradicate the disease, the team at Target Malaria will probably deserve a big share of the credit. Their plan to use gene drive technology to wipe out species of mosquitoes carrying the parasitic illness represents the most promising path to eradicating a disease that killed on the order of 150 million to 300 million people over the 20th century, and still kills hundreds of thousands each year.
Malaria used to be broadly common across most of the populated world, covering much of North America, Europe, Japan, and Australia, in addition to its current locations in Africa, Latin America, and South Asia. As the researchers Max Roser and Hannah Ritchie note, “poet Friedrich Schiller contracted the disease in Mannheim, Oliver Cromwell in Ireland, and Abraham Lincoln in Illinois.” Malaria no longer exists in those areas due to decades of public health measures like the drainage of mosquito breeding sites and use of pesticides like DDT, as well as economic development that gave residents resources to prevent and treat the disease.
But that kind of economic growth has proven stubbornly elusive in many countries in sub-Saharan Africa, where over 90 percent of all malaria deaths occur. Poor governments in the region struggle to provide sufficient preventive measures like prophylactic drug treatments and insecticidal bednets.
That’s where Target Malaria comes in. The group has been conducting meticulous research for years on the viability of using a gene drive, a kind of self-propagating genetic alteration that altered organisms pass along to all their offspring, to wipe out three specific species of mosquito responsible for the majority of the disease’s transmission. These represent a tiny fraction of the 3,500 mosquito species on Earth, but a gene drive that prevents these three species from producing new females (only females bite humans) could dramatically reduce malaria transmission, faster and cheaper than any other method.
Obviously, the task of wiping out whole species of mosquitoes should not be undertaken lightly, and Target Malaria is scrupulous, moving very slowly and beginning by studying genetically modified mosquitoes that are not gene drive mosquitoes (and thus do not rapidly spread their genetic change throughout the population), such as the sterile male mosquitoes it released in a controlled setting in Burkina Faso in 2019. The group’s insectary in Burkina Faso recently received mosquitoes (again, not gene drive mosquitoes) modified to have “male bias,” meaning they have been engineered to produce mostly male offspring. These modified mosquitoes have not been released yet, and only after they’ve undergone a controlled release and the group has collected data would an actual gene drive trial be on the table.
Perhaps most importantly, Target Malaria is a project meant to benefit the people of sub-Saharan Africa that is led in substantial part by African scientists. Its four country leads are all experienced scientific researchers based at African institutions: Jonathan Kayondo of the Uganda Virus Research Institute, Fred Aboagye-Antwi of the University of Ghana, Mamadou Coulibaly of the University of Bamako in Mali, and Abdoulaye Diabate of the Research Institute in Health Sciences in Burkina Faso. Global North universities help, especially in producing the modified mosquitoes, but the on-the-ground work is overwhelmingly done by and for Africans.
That model has not been the norm in global public health in the past, to say the least. And Target Malaria’s commitment to letting African communities decide how to deal with one of their gravest threats makes the effort that much likelier to succeed.
