African scientists are developing an innovative technique capable of eradicating malaria-carrying mosquitoes by altering their genes.
According to the World Health Organization (WHO), malaria is the leading cause of death in Burkina Faso, where nearly the entire population of 22 million, particularly children, are at risk of the disease. The latest data from WHO’s Africa regional office indicates that malaria killed nearly 19,000 people in Burkina Faso in 2021.
This disease is also one of the main causes of death in the African region, which bears the largest malaria burden in the world.
A child in Malawi receiving a malaria vaccine during a pilot program on December 11, 2019. (Source: AP).
For many years, malaria prevention interventions, including the use of insecticide-treated bed nets, have helped reduce transmission and mortality in affected countries. However, “malaria-related deaths remain at unacceptably high levels, and cases have continued to rise since 2015,” the WHO stated in April, asserting that the increase in infections is due to rising costs of providing interventions and “biological threats” posed by drug resistance, allowing malaria-carrying mosquitoes to develop immunity to insecticides.
According to WHO data, malaria killed approximately 619,000 people worldwide in 2021, with 96% of these deaths occurring in Africa, while 80% of malaria cases on the continent involve “children under 5 years old.”
Mr. Diabate, head of the entomology and medical parasitology department at the Burkina Faso Institute for Health Science Research, emphasizes that innovating malaria control tools is the only way to conquer this disease.
“While insecticide-treated bed nets have been effective, there is currently widespread resistance among various mosquito species, especially those that transmit malaria. This complicates efforts to defeat malaria using conventional tools. This is why innovating and developing new tools to complement existing ones is critically important. Without it, we will not be able to defeat malaria,” Mr. Diabate stated.
Diabate expressed optimism about his malaria control tool, described as “gene drive technology,” which could become a “game changer” once deployed.
Malaria is transmitted through the bite of infected female Anopheles mosquitoes. Male mosquitoes do not bite, so they cannot transmit malaria. With gene drive technology, malaria-carrying female mosquitoes will be unable to reproduce after genetically modified sterile males are released into the environment. This will lead to a decline in the female mosquito population, halting malaria transmission.
Mr. Diabate stated: “When the (genetically modified) mosquitoes are released into the fields, they will integrate into the mosquito population and immediately reduce malaria transmission. The gene drive effort is a more sustainable and cost-effective malaria control intervention.”
“The benefit of the technology we are developing is that if it is activated and functions as expected, it will not only save costs but also be sustainable and can be implemented in remote and hard-to-reach areas in Africa. We believe that once the technology is ready, it could become a game changer,” Mr. Diabate remarked about the optimization of the new technology. However, he noted that it may take several more years to deploy gene drive technology in Africa.
In 2013, Oxitec, a U.S. biotechnology company, created a genetically modified mosquito that transmits a self-limiting gene to female Aedes aegypti mosquitoes, which transmit yellow fever, dengue fever, and Zika virus. As a result, the offspring of the genetically modified females die at the larval stage.
In 2016, the International Atomic Energy Agency implemented a technique using X-rays to sterilize male mosquitoes in Latin America and the Caribbean, aiming to reduce the reproductive capacity of female mosquitoes that transmit the Ebola virus.
Mr. Diabate’s research is among the first to use gene editing technology targeting male mosquitoes.
Health agencies outside Burkina Faso have welcomed Mr. Diabate’s gene drive technology but remain concerned about its environmental impact when fully applied.
Mr. Lumbani Munthali, manager of the National Malaria Control Program in Malawi, stated that while gene drive technology is “a good innovation and coming at the right time,” its ecological impact has yet to be clearly assessed.
The Save Our Seeds (SOS) advocacy group based in Germany has campaigned against gene drive technology, arguing that the impacts of this technology on the ecosystem are unpredictable.
On its website, SOS states: “Every living organism, even those that seem dangerous or harmful to humans, performs important roles in the ecosystem. Therefore, eradicating or even manipulating a species will have consequences for the entire ecosystem.”
The advocacy group explains that mosquitoes are a primary food source for many animals, such as birds and dragonflies, and recalls that in Camargue, a nature reserve in southern France, the eradication of mosquitoes using biological agents led to declines in both the numbers and diversity of bird and dragonfly species.
Mr. Munthali argues: “Gene drive technology involves modifying genetic material, so you never know what new vectors you might create and how that will impact the environment and ecosystem. This is something researchers need to consider.”
