Mosquitos are our dire enemy, but how do we fight such a highly successful organism?
In the wake of Zika and renewed outbreaksof Dengue fever, scientists are turning to
new management methods -- including using factories to mass-breed
genetically modified mosquitoes.
You're familiar with the problem: Mosquitoes
suck our blood, and in doing so they serve
as a perfect blood-bridge from individual
to individual, spreading deadly pathogens
such as yellow fever, Zika, Dengue, malaria,
West Nile and more.
And all they need to reproduce is the tiniest
bit of water for their larvae.
Manage standing water all you want, dust their
environment -- and yours -- with pesticides,
but these most-perfect organisms boast an
incredible ability
to bounce back from such efforts.
And that's one reason for the mosquito factories.
They're scientific projects aimed at pumping
out altered mosquitoes to compete with the
populations that pose a threat.
One such project in Guangzhou, China, has
reported promising results.
They're rearing and releasing mosquitos infected
with Wolbachia bacteria --
and for two very good reasons.
First, the it renders the mosquitoes incapable
of carrying a wide range of dangerous pathogens
-- a quirk the mosquitoes pass on to their
offspring.
Again, the strategy is the same: Breed THESE
compromised mosquitoes and allow them
to overwhelm their disease-spreading brethren.
And that's where the second reason comes into
play:
Wolbachia helps to curb overall population as well.
When a male Wolbachia-infected mosquito mates
with an uninfected female,
the resulting eggs don't hatch.
Only when both mates carry Wolbachia does
the union result in viable eggs, which pass
on the infection -- which, by the way, does
not transfer to people.
According to the Atlantic, the Guangzhou project
claims a 99 percent suppression rate in localized
tests, and a similar project is underway in
Australia.
The British biotechnology company Oxitec has
an even more futuristic tactic: flood the
mosquito population with genetically-modified
mosquitoes
that die four days later and produce offspring that die as larvae.
They've been pumping these doomed GMOsquitoes
out in Brazil to the tune of two million bugs
a week -- and, as reported in Technology Review,
they've seen impressive drops in Dengue fever
cases as a result.
Some scientists hold out hope that such gene
editing could even be used to
drive mosquitoes into extinction. Now, as great as that sounds,
not everyone's crazy about mosquito extinction
 -- even if we're only talking about
the couple hundred or so species -- out of
3,500 -- that actually pester humans.
They might be pests, but they also make up
a great deal of biomass, and as such serve
as food for various predators.
Wipe them out and you potentially unbalance
the ecosystem.
And not everyone's crazy about the GMO thing
either, especially in species so intimately
connected to our own blood supply.
More reasonable critics question a commercial
company's use of proprietary gene codes to
combat illness, while conspiracy theorists
in Brazil have even gone so far as to, erroneously,
blame Zika on genetically-modified mosquitoes.
Hey, until vaccination catches up with the
threat, all options remain on the table -- and
the resulting advancements redefine just how
humans manipulate every detail of their environment.
So which mosquito-curbing method do you prefer? Let us know.
And if you want more weird science wonder,
be sure to check out now.howstuffworks.com
each and every day.
