Scientists at MIT are proposing the use of a controversial “gene drive” technology to wipe out the mosquitoes that carry the Zika virus, the rapidly spreading illness that causes babies to be born with small heads and brains. Three U.S. labs that handle mosquitoes are now working on developing the gene drive for the Aedes aegypti mosquito species, which also spread dengue fever and yellow fever. Researchers say the technology could be ready in as little as a few months, but they warn it will need to go through rigorous testing before it can be used to combat the disease-carrying insects.
The Zika virus stemmed from a few cases in Brazil and has exploded throughout Central and South America and into the United States. Current estimates identify around 4,000 cases of children born with microcephaly in Brazil as the result of the Zika virus, which their mothers contracted during pregnancy via a mosquito bite. There is no vaccine and no cure, and the rapid spread of the virus has prompted health officials throughout South America to warn women to avoid pregnancy until threat of the birth defect has waned. Although there have been only a dozen or so cases identified so far in the United States, President Barack Obama has asked Congress for $1.8 billion to combat the virus, by accelerating mosquito control programs, funding vaccine research, and providing additional health services to low-income pregnant women. Part of Obama’s plan calls for extended financial support to other countries where the Zika outbreaks have been widespread.
Although scientists say the gene drive could be ready soon, it could be years before the technology is actually put into use. MIT acknowledges that the technique is controversial, and that releasing it “in the wild” will raise concerns among ecologists. To that end, researchers expect the gene drive to undergo testing – say, on an isolated island – before it could be introduced to mosquito populations at large.
The gene drive technology, when its development is complete, would work in one of two ways. Scientists can engineer the mosquito’s genetic material so that they are unable to carry the Zika virus, similar to the breakthrough made last year that could block mosquitoes from carrying malaria. The second option is to manipulate reproduction so that only male mosquitoes are produced, leading to extinction after a few short generations. Either way, the decision to implement the gene drive isn’t up to the scientists, so ecologists and public health officials will have to sign off on the approach.
Lead image via Shutterstock