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Zika fever:
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our newest dread disease.
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What is it? Where'd it come from?
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What do we do about it?
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Well for most adults,
it's a relatively mild disease --
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a little fever, a little headache,
joint pain, maybe a rash.
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In fact, most people who get it
don't even know they've had it.
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But the more we find out
about the Zika virus
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the more terrifying it becomes.
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For example, doctors
have noticed an uptick
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of something called Guillain-Barré
syndrome in recent outbreaks.
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In Guillain-Barré, your immune system
attacks your nerve cells
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it can partially
or even totally paralyze you.
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Fortunately, that's quite rare,
and most people recover.
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But if you're pregnant
when you're infected
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you're at risk of something terrible.
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Indeed, a child with a deformed head.
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Here's a normal baby.
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Here's that infant
with what's called microcephaly.
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a brain in a head that's too small.
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And there's no known cure.
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It was actually doctors
in northeastern Brazil
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who first noticed, just a year ago,
after a Zika outbreak,
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that there was a peak
in the incidence of microcephaly.
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It took medical doctors another year
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to be sure that it was caused
by the Zika virus,
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but they're now sure.
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And if you're a "bring on
the evidence" type,
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check out this publication.
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So where did it come from,
and how did it get here?
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And it is here.
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Like many of our viruses,
it came out of Africa,
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specifically the Zika forest in Uganda.
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Researchers at the nearby
Yellow Fever Research Institute
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identified an unknown virus
in a monkey in the Zika forest
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which is how it got its name.
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The first human cases of Zika fever
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surfaced a few years later
in Uganda-Tanzania.
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The virus then spread through West Africa
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and east through equatorial Asia --
Pakistan, India, Malaysia, Indonesia.
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But it was still mostly in monkeys
and, of course, mosquitoes.
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In fact in the 60 years between the time
it was first identified in 1947 and 2007
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there were only 13 reported cases
of human Zika fever.
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And then something extraordinary happened
on the tiny Micronesian Yap islands.
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There was an outbreak that affected
fully 75 percent of the population.
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How did it get there? By air.
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Today we have two billion
commercial airline passengers.
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An infected passenger can board a plane,
fly halfway around the world
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before developing symptoms --
if they develop symptoms at all.
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Then when they land, the local mosquitoes
begin to bite them and spread the fever.
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Zika fever then next surfaced
in 2013 in French Polynesia.
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By December of that year, it was being
transmitted locally by the mosquitoes.
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That led to an explosive outbreak in which
almost 30,000 people were affected.
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From there it radiated around the Pacific.
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There were outbreaks in the Cook
Islands, in New Caledonia,
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in Vanuatu, in the Solomon Islands
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and almost all the way around to the coast
of South America and Easter Island.
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And then, in early 2015,
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there was an upsurge of cases
of a dengue-like syndrome
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in the city of Natal
in northeastern Brazil.
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The virus wasn't dengue, it was Zika,
and it spread rapidly --
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Recife down the coast, a big metropolitan
center, soon became the epicenter.
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Well people have speculated that it was
2014 World Cup soccer fans
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that brought the virus into the country.
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But others have speculated that perhaps
it was Pacific Islanders
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participating in championship canoe races
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that were held in Rio that year
that brought it in.
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Well today, this is only a year later.
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The virus is being locally transmitted
by mosquitoes
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virtually throughout South America,
Central America, Mexico
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and the Caribbean Islands
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Until this year, the many
thousands of cases
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that have been diagnosed in the US
were contracted elsewhere.
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But as of this summer, it's being
transmitted locally in Miami.
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It's here.
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So what do we do about it?
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Well, preventing infection
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is either about protecting people
or about eliminating the mosquitoes.
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Let's focus on people first.
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You can get vaccinated.
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You can not travel to Zika areas.
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Or you can cover up
and apply insect repellent.
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Getting vaccinated is not an option,
because there isn't a vaccine yet
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and there probably won't be
for a couple of years.
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Staying home isn't
a foolproof protection either
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because we now know that
it can be sexually transmitted.
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Covering up and applying
insect repellent does work ...
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until you forget.
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(Laughter)
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So that leaves the mosquitoes,
and here's how we control them now:
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spraying insecticides.
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The protective gear is necessary
because these are toxic chemicals
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that kill people as well as bugs.
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Although it does take quite a lot more
to kill a person than to kill a bug.
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These are pictures from
Brazil and Nicaragua.
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But it looks the same in Miami, Florida.
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And we of course can spray
insecticides from planes.
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Last summer, mosquito control officials
in Dorchester County, South Carolina,
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authorized spraying of Naled,
an insecticide,
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early one morning,
as recommended by the manufacturer.
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Later that day, a beekeeper told reporters
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that her bee yard looked
like it had been nuked.
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Oops.
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Bees are the good guys.
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The citizens of Florida protested,
but spraying continued.
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Unfortunately, so did the increase
in the number of Zika fever cases.
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That's because insecticides
aren't very effective.
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So are there any approaches that are
perhaps more effective than spraying
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but with less downsides
than toxic chemicals?
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I'm a huge fan of biological controls,
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and I share that view with Rachel Carson,
author of "Silent Spring,"
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the book that is credited with starting
the environmental movement.
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In this book she tells the story,
as an example,
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of how a very nasty insect
pest of livestock
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was eliminated in the last century.
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No one knows that
extraordinary story today.
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So Jack Block and I,
when we were writing an editorial
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about the mosquito problem today,
retold that story.
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And in capsule form, it's that pupae --
that's the immature form of the insect --
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were irradiated until they were sterile,
grown to adulthood
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and then released from planes
all over the Southwest,
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the Southeast and down into Mexico
and into Central America
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literally by the hundreds of millions
from little airplanes,
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eventually eliminating
that terrible insect pest
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for most of the Western Hemisphere.
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Our real purpose in writing this editorial
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was to introduce readers
to how we can do that today --
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not with radiation
but with our knowledge of genetics.
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Let me explain.
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This is the bad guy: Aedes aegypti.
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It's the most common insect
vector of diseases,
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not just Zika but dengue,
Chikungunya, West Nile virus
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and that ancient plague, yellow fever.
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It's an urban mosquito,
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and it's the female
that does the dirty work.
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She bites to get a blood meal
to feed her offspring.
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Males don't bite; they don't even
have the mouth parts to bite.
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A little British company called Oxitec
genetically modified that mosquito
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so that when it mates with a wild female,
its eggs don't develop to adulthood.
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Let me show you.
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This is the normal reproductive cycle.
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Oxitec designed the mosquito so that
when the male mates with the wild female
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the eggs don't develop.
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Sounds impossible?
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Well let me show you
just diagrammatically how they do it.
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Now this represents the nucleus
of a mosquito cell,
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and that tangle in the middle
represents its genome,
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the sum total of its genes.
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Scientists added a single gene
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that codes for a protein represented
by this orange ball
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that feeds back on itself
to keep cranking out more of that protein.
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The extra copies, however,
go and gum up the mosquitoes' genes,
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killing the organism.
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To keep it alive in the laboratory
they use a compound called tetracycline.
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Tetracycline shuts off that gene
and allows normal development.
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They added another little wrinkle
so that they could study what happens.
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And that is they added a gene
that makes the insect glow under UV light
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so that when they released it
they could follow exactly how far it went
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how long it lived
and all of the kinds of data
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for a good scientific study.
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Now this is the pupal stage,
and at this stage
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the females are larger than the males.
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That allows them to sort them
into the males and the females
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and they allow only the males
to grow to adulthood.
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And let me remind you
that males don't bite.
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From there it's pretty simple.
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They take beakers full of male mosquitoes,
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load them into milk cartons,
and drive around the city,
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releasing them guided by GPS.
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Here's the mayor of a city
releasing the first batch
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of what they call the "friendly Aedes."
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Now I wish I could tell you
this is an American city, but it's not.
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It's Piracicaba, Brazil.
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The amazing thing is that in just a year
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it brought down the cases
of dengue by 91 percent.
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That's better than any insecticide
spraying can do.
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So why aren't we using this remarkable
biological control in the US?
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That's because it's a GMO:
a genetically modified organism.
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Notice the subtitle here says
if the FDA would let them
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they could do the same thing here,
when Zika arrives.
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And of course it has arrived.
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So now I have to tell you the short form
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of the long, torturous story
of GM regulation in the US
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In the US, there are three agencies that
regulate genetically modified organisms:
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the FDA, the Food and Drug Administration,
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the EPA, the Environmental
Protection Agency,
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and the USDA, US Department
of Agriculture.
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Took these folks two years
to decide that it would be the FDA
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that would regulate the genetically
modified mosquito.
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And they would do it as a new animal drug,
if that makes any sense.
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Took them another five years going back
and forth and back and forth
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to convince the FDA
that this would not harm people,
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and it would not harm the environment.
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They finally gave them, this summer,
permission to run a little test
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in the Florida Keys,
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where they had been invited years earlier
when they Keys had an outbreak of dengue.
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Would that it were that easy.
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When the local residents heard
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that there would be genetically modified
mosquitoes tested in their community
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some of them began to organize protests.
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They even organized a petition on
the internet with this cuddly logo,
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which eventually accumulated
some 160,000 signatures
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And they demanded a referendum
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which will be conducted
in just a couple of weeks
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about whether the trials
would be permitted at all.
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Well it's Miami that really needs
these better ways of controlling insects.
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And there the attitudes are changing.
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In fact, very recently a bipartisan group
of more than 60 legislators
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wrote to HHS Secretary Sylvia Burwell
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asking that she, at the Federal level,
expedite access for Florida
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to this new technology.
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So the bottom line is this:
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biological control of harmful insects
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can be both more effective and
very much more environmentally friendly
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than using insecticides,
which are toxic chemicals.
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That was true in Rachel Carson's
time; it's true today.
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What's different is that we have
enormously more information
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about genetics than we had then,
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and therefore more ability
to use that information
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to affect these biological controls.
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And I hope that what I've done
is aroused your curiosity enough
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to start your own inquiry --
not into just GM mosquitoes
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but to the other genetically modified
organisms that are so controversial today.
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I think if you do that, and you dig down
through all of the misinformation,
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and the marketing
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on the part of the organic food industry
and the Greenpeaces
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and find the science,
the accurate science,
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you'll be surprised and pleased.
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Thank you.
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(Applause)