Destroying the mosquito population may soon become more than just a dream for the bug-averse.
The plan could become reality in the Florida Keys, where Intrexon Corporation’s Oxitec Ltd…has proposed letting genetically-engineered mosquitoes free in a bid to cut down on the Aedes aegypti strain, which transmits the Zika virus, among other mosquito-borne diseases.
If allowed, it would be the first time something like this is tried with mosquitoes in the U.S., and is aimed not at the recent surge in the Zika virus in Latin America but rather at dengue fever, another mosquito-borne disease that flared up in the U.S. in 2009 after decades of inactivity.
Oxitec calls its mosquitoes “self-limiting”: the male mosquitoes are genetically bred so when they mate with female mosquitoes, the offspring die. The male mosquitoes die off, too, so within six to eight weeks, the mosquitoes and their progeny are gone.
Mosquitoes seem like a prime candidate for eradication. Beneath their merely pesky appearance lies a disease-spreading agent, responsible for transmitting Zika virus and dengue but also chikungunya, West Nile virus, yellow fever and malaria.
But could getting rid of the pests have other consequences? A preliminary finding by the Food and Drug Administration’s Center for Veterinary Medicine suggested Oxitec’s experiment would have “no significant impact” on the environment, though it noted findings “may change on further review.”
A 2010 article in science journal Nature found that in a world without mosquitoes, “Life would continue as before—or even (be) better.”
Oxitec’s trial is just that: a short-term experiment. With approval, it could last up to 22 months in a designated trial site. The company has been able to achieve mosquito population control in six to nine months in trials in other countries (including the Cayman Islands, Panama and Brazil), said Derric Nimmo, Ph.D., the company’s product development manager.
After that, without additional releases, the mosquito population would recover.
Still, opposition remains: there are local, vocal objections, and nearly 10,000 people have signed an online petition opposing the trial. Sponsored by the nonprofit Center for Food Safety, it compares the experiment with “the plot to a new Jurassic Park” and says it is “simply too risky for our environment and public health and is fraught with many unanswered questions.”
Oxitec has been working since before 2009 on this trial, which it has run past the Food and Drug Administration, the Centers for Disease Control and Prevention and the Environmental Protection Agency, said Oxitec’s Nimmo.
The FDA’s preliminary findings are currently open for a comment period. Then it could be three months to a year before the agency delivers its final assessment, Nimmo said, adding “but don’t hold me to that.”
In any case, large-scale “self-limiting” mosquito control is still years away, Nimmo said, though it’s possible the company could get emergency permissions if a U.S. Zika outbreak occurs.
Zika is expected to travel to the U.S., though there haven’t been any locally-spread cases yet. Causing symptoms such as fever, rash, muscle pain and headaches, the disease has also been connected to a paralyzing autoimmune disease, birth defects in pregnant women’s children and, most recently, a brain disease much like multiple sclerosis, the New York Post reported.