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.
XON, +2.99%
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.
Read more:
What exactly is the Zika virus, and why should you care?
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.
See:
Is it time to just wipe out mosquitoes?
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.
Officials at the Centers for Disease Control and Prevention
said last
week that the disease’s effects are “scarier than we initially
thought.” Aedes aegypti is present in about 30 states, the CDC’s
principal deputy director said, more than double the initial number of
12 states. The Obama administration has requested billions of dollars to
fight the disease.
To be sure, there may be no perfect way of getting to a mosquito-free world.
Genetic
modification plans are expensive and effective only for a limited time,
Jeff Powell, a Yale University biology professor and mosquito expert
told MarketWatch in an interview earlier this year.
The method also only
keeps the population down when constantly used.
Powell
is researching a method he believes is more sustainable: working with
mosquitoes’ naturally-occurring genetic variation to change their
disease-transmission abilities. The idea, though compelling, could take
several years at least to get off the ground, Powell said.
But
Nimmo said Oxitec’s technology wouldn’t cost any more than the $1.1
million the Keys spends on Aedes aegypti control already, “and we would
be able to get greater than 90% control.”
The cost also ensures
that so-called self-limiting mosquitoes would only be justified in areas
severely threatened by mosquito-borne disease outbreaks, with some
examples including Texas, Hawaii and Puerto Rico.
It’s also only intended for Aedes aegypti.
As for the other types of mosquitoes, might we suggest aloe vera?
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