People across the world conceive mosquitoes exclusively as pests. They are abundant in humid regions of the world, leaving itchy bite marks and often spreading deadly diseases to humans and other animals alike. Considering this fact, it isn’t strange that several people have considered the premise of eradicating mosquitoes from Earth, including several brilliant genetic scientists across the world, who have developed artificially modified mosquitoes to slowly whittle down their population, preventing the spread of deadly diseases in remote parts of the world. This is a vital step in the Target Malaria project, funded largely by the Bill & Melinda Gates Foundation.
The Aedes aegypti mosquito is known to spread diseases such as Zika, Dengue, Malaria, among others. It has spread across the world, originating from sub-Saharan Africa.
The Method of Eradication
According to the NPR, researchers from the United Kingdom developed the mosquitoes using a technique called CRISPR, which allows one to cut out and modify a specific portion of the DNA. In short, it is an artificial gene editing tool. Traditionally, this tool, apart from creating the desired traits, is used to prevent the spread of artificial genes in the event of a leak or escape of the subjects. However, this time around, their goal is to spread the gene as much as possible.
Researchers concluded that the most harmless and risk free solution to reducing the mosquito population was to prevent further generations from reproducing. There are two different groups approaching this problem. One is a company called Oxitec, which has developed a mosquito that produces a protein during fertilization that kills off any female mosquitoes from being born; a more direct and fast-acting approach. This method has already been applied in countries such as Brazil, even receiving a green light to be released into the Florida Keys. The responsible entity, Oxitec, has responded against backlash that they have released more than a billion mosquitoes over the years, and no adverse effects have been observed as of yet.
The other solution has been developed by researchers in a secure lab in Terni, Italy. The gene that they have developed not only modifies the mouth of the female mosquito, making it unable to bite humans, it also deforms their reproductive system. Back at the start of 2019, isolated trials of these mosquitoes were being held in the lab in order to observe adverse effects of the gene being introduced into an existing population. Likewise to the former example, this approach of artificially modifying mosquitoes has also been faced with outcries from environmental groups and experts, who have cited the potential of new mosquito species being introduced, and farms falling behind in productivity due to the lack of pollinators. Nevertheless, experts such as Kevin Esvelt, an evolutionary engineer at the Massachusetts Institute of Technology, have expressed support for the project, stating that the benefits of eliminating malaria “outweighs the combined harms of everything that has been postulated could go wrong ecologically”.
Above is a map showing the distribution of the Aedes aegypti species across the world as of 2015.
Despite the constant controversy around exterminating an entire species, and releasing genetically modified species into the wild, a frightening premise by itself, these projects will most likely continue in development far into the future. Both projects, despite approaching the problem from different directions, show a promising future in preventing the spread of mosquito-borne diseases. Whether it be a gradual eradication of a species through minor physiological changes, or an abrupt sterilization of a species, the eradication of malaria is a promising future worth pursuing.