Engineered Mosquitoes Could Wipe Out Dengue Fever

Christina Valencia points us to a Wired story about scientists who plan to use genetically modified mosquitoes to reduce the population of Dengue-carrying insects. The altered genes cause newly born mosquitoes to die before they are able to breed if they are not supplied with a crucial antibiotic. This is a more aggressive approach than the anti-Malaria work we discussed last year. From Wired: "Mosquitoes pass dengue fever to up to 100 million people each year, according to the Centers for Disease Control and Prevention. Up to 5 million die. If the scientists can replicate their results in real field conditions, their technology could kill half of the next generation of dengue mosquitoes, which scientists say would significantly reduce the spread of the disease. If all goes well the company envisions releasing the insects in Malaysia on a large scale in three years."

Comments

Didn't we learn

[PachmanP]

...from Jurassic Park!
A specific protein in the movies vs an anti-biotic in real life!

I guess I welcome our genetically engineered super mosquito overlords!

Re:Didn't we learn

[Lemmy Caution]

I can't believe that this hasn't been pasted in yet: (from "Bart the Mother")

Skinner: Well, I was wrong. The lizards are a godsend.
Lisa: But isn't that a bit short-sighted? What happens when we're overrun by lizards?
Skinner: No problem. We simply release wave after wave of Chinese needle snakes. They'll wipe out the lizards.
Lisa: But aren't the snakes even worse?
Skinner: Yes, but we're prepared for that. We've lined up a fabulous type of gorilla that thrives on snake meat.
Lisa: But then we're stuck with gorillas!
Skinner: No, that's the beautiful part. When wintertime rolls around, the gorillas simply freeze to death.

Re:Didn't we learn

[Rei]

Seriously, it won't work unless its done every year

Well, there's an easy solution for that. Genetically engineer them to make them go extinct.

This article on Slashdot is proposing something a *lot* more tame than the specicide proposal. Basically, most genes have a 50% chance of passing on to offspring, but certain "selfish" genes game the system and all but guarantee that they're passed along. So, you make a selfish, lethal, recessive gene -- that is, a mosquito can have one copy and survive just fine. When it mates with a wild mosquito, it'll produce offspring that almost all have the recessive, lethal gene. This will continue until most of the wild population now has the gene -- and then they all start dying off. They can no longer interbreed.

Because it sweeps through so fast, there's no chance to adapt resistance. The only thing that can save the species is isolated pockets that manage not to interbreed with the outside world, then escape after all of the others are dead. Hence, effective, widespread distribution of the engineered individuals is critical for complete specicide. As for side-effects, not only has localized extinction of the Anopheles mosquito not had any adverse impact on the ecosystem (other insects fill in the gap on the food chain), but current control attempts are not mosquito-specific; they kill *many* species in large numbers, and we do it every year.

Ripple Effect

[Doc Ruby]

Those mosquitoes might suck (pun intended :P), but they're food for a lot of animals that don't suck. If we just eliminate all the mosquitoes, we probably can't tell how we'll affect the rest of the ecosystem. Eliminating the dengue fever germs will have its effect, but I'm not too worried about depriving the worms of the corpses they're used to growing fat on.

Re:Ripple Effect

[Dutch Gun]

I'm fairly certain that if someone you cared deeply for was at serious risk of catching Dengue, you really wouldn't give care quite as much how the ecology would fare without those mosquitoes.

Oh, and take a walk out in a tropical region sometime. You'll quickly realize that the notion of the eco-chain being in any significant peril because one species of insect disappears is a bit far-fetched, I think. The number of insects (both in general number as well as the number of species) is pretty staggering. Species have disappeared all throughout history, and nature is fabulous at filling available niches.

I'd have no hesitation in pulling the trigger if it mean eliminating every damn mosquito on earth. Sorry if that sounds unenlightened.

Re:Ripple Effect

[NeutronCowboy]

I'd have no hesitation in pulling the trigger if it mean eliminating every damn mosquito on earth. Sorry if that sounds unenlightened.

It's not unenlightened, it's stupid. It displays a staggering ignorance of the effect of introducing foreign species in a new environment (Northern Pike, rabbits, zebra mussel, spanish moss, etc. etc. etc.) or of removing one species from an ecosystem (grizzly bear, star fish, kelp, etc, etc, etc). Finally, you completely overestimate the redundancy and resilience of the tropical rain forests (hint: one controlled burn sets an area back about 400 years in terms of return to normal) and underestimate its complexity (hint: what's the impact of removing fire ants from the system?).

Feel free to google the terms. I've set you up with enough key terms that you can educate yourself on the impact. The basic point is that we, as a species, have optimized our behavior to the world as it is. Removing (or adding) to our system can have an impact that goes far beyond expectations, with an impact that is staggering in cost. Think Jenga on a global scale.

Re:Ripple Effect

[Doc Ruby]

Not only have I taken a walk in a tropical region, I lived in Southeast Louisiana for years, which is thousands of miles of swamp. I actually got an unidentified virus in Africa most probably from one of the many mosquitoes who bit me while I slept near the Niger River. In New Orleans, we eliminated centuries of Yellow Fever by draining the swamps, not by targeting a species with untested genetic engineering weapons. But even that action has had consequences to the rest of the ecosystem, though at the more familiar level of drainage and flooding.

Fortunately, public health decisions aren't made by one guy calling themself "Dutch Gun" who wants to just walk around pulling triggers because of their single personal benefit.

Instead, people with that kind of power typically don't make decisions with at the neural level that slaps at a sting. Instead we think of the actual costs of human intervention, and how that's different from the more integrated processes in nature eliminating species, and learning from when it's the same, and causes a ripple effect that we'd rather not be injured by.

Biology is perhaps the most complex studyable natural system. Ecosystems are the most complex interactions of biological systems. We have to consider what an apparently "simple", drastic action that destroys an entire species that other species depend on will actually do, before we do it.

Re:Ripple Effect

[Dutch Gun]

Brilliant straw-man argument there. You now have me burning down forests, killing grizzly bears, starfish, kelp, and other highly important and relevant species that would obviously have a devastating impact on the environment were they suddenly removed. And yes, I'm well aware that size alone does not necessarily dictate importance in the larger scheme of things (e.g. ocean plankton). But the notion that every single species is equally vital to the ecosystem is simply fallacious to any reasoning mind.

Yes, I'm well aware of the dangers of introducing species to new areas or making changes of any sort of an ecosystem. I just happen to think that saving so many human lives is worth the risk in this case. I'm sorry you don't feel the same way.

But... what's the long term impact of this?

[drspliff]

I really don't know enough to speculate, but one question is: what's the long term ecological and biological impact going to be?

If these things don't breed... then they start dying off? Then what happens when the mosquito population severly reduced, will other insects take their place, or will the ones naturally immune to this grow bigger etc...

Although, a world without mosquitos would be nice :D

Re:But... what's the long term impact of this?

[Mr. Roadkill]

And what about places like Hawaii, where there were no mosquitoes until they were introduced by man? Hawaiian biota managed to do just fine before mosquitoes were introduced. Surely it wouldn't be a terrible thing to eradicate them there?

Eradicating mosquitoes in Hawaii probably wouldn't cause a major ecological disruption - unless the mosquitoes themselves had completely displaced some other organism in some niche (as either prey or predator) - but it's harder to say what would happen elsewhere. What happens to all the things that eat mosquitoes and mosquito larvae if there aren't any mosquitoes? Also, for much of the time, mosquitoes are nectar-feeders too - so if there are plants that depend primarily on mosquitoes for pollination, there could be an impact on organisms that depend on those plants. Sure, life adjusts, and a new equilibrium is established - eventually. That still doesn't mean we shouldn't be damn careful, because in the meantime there's a chance that we could do something that we'd find extremely inconvenient or unfortunate.

Crucial antibiotic...

[boundary]

Jesus, I hope they don't start raiding pharmacies for their fix!

Whatcouldpossiblygowrong

[caller9]

Am I the only one that's noticed a ton of these "whatcouldpossiblygowrong" tags recently. Did the mad scientist class of '07 get to work quickly or what? Who is throwing all this money at applying knowledge we barely have to applications we can't imagine the repercussions of. Some of this stuff could turn out a little worse than introducing cats to Australia, if you catch my meaning.

Are mosquitos important?

[rastoboy29]

I have often wondered (living in the mosquito-ridden South), if mosquitoes have any benefit to the ecosystem at all.  We often hear about how if you remove one creature from the ecosystem, the whole thing changes.  But mosquitoes?  I'm not sure they would be missed by any creature. 

Re:Are mosquitos important?

[Whiney Mac Fanboy]

I have often wondered (living in the mosquito-ridden South), if mosquitoes have any benefit to the ecosystem at all.

Bottom line is that Mosquito larvae are extremely beneficial to ecosystems (as food). Read this for a quick overview. Contains the quote:

mosquito larvae might be pictured as: "small machines that transform algae, bacteria and organic matter into compact packages of protein.

If you want to read something a little more specific to the south, try this Mosquito Virtues article.

Re:Are mosquitos important?

[MichaelSmith]

Bottom line is that Mosquito larvae are extremely beneficial to ecosystems (as food)

Back when my wife and I had just bought our house I installed two small ponds. Within days we were being bitten alive by mosquitoes. You could see the larvae swimming around in the ponds. We went down to the local creek and returned with a couple of dozen small fish. Within two days we had our result. Hardly any mozzies and fish twice the size.

Re:Are mosquitos important?

[DieByWire]

I have often wondered (living in the mosquito-ridden South), if mosquitoes have any benefit to the ecosystem at all. We often hear about how if you remove one creature from the ecosystem, the whole thing changes. But mosquitoes? I'm not sure they would be missed by any creature.

There are many species of mosquitos, not all (or even most IIRC) of which bite humans. There's no need - and no way - to wipe out all mosquitos. Hammering the specific species that transmit deadly diseases to humans is an ecological engineering project and moral choice that I think most humans are comfortable with, though.

The effort in the article specifically attacks one species - the Aedes aegypti mosquito.

Re:Genetically Engineered Mosquitoes

[Whiney Mac Fanboy]

That sounds suspiciously like an urban legend.

Hint: How the fuck are you supposed to breed lovebugs & mosquitoes? (Give them tiny little Jacuzzis and Play Barry White at them?)

Won't Work

[theshibboleth]

I don't really understand how the company can expect this approach to work. From the article:

Oxitec's technique is considered less controversial by some scientists because the genetically modified insects are programmed to die, not take over the existing mosquito population.

If the modified mosquitoes are to have any effect they must replace the wild mosquitoes. Otherwise, the wild mosquitoes will still continue to transmit dengue to humans. The article doesn't say whether offspring of wild and modified mosquito live long enough to breed nor what proportion of them still depend on tetracycline, but if you have two populations, one that dies young and another that doesn't and is thus able to breed longer, the longer-lived population will outcompete the short-lived one. Thus if the goal of this is replacement, that too would not work. At best they could hope to kill off maybe half of the mosquito population and thereby reduce dengue fever in the short-term, but doing so could unbalance the ecosystem and potentially have negative effects, including disease, for humans. Maybe a better approach would be to create mosquitoes that only die if they are infected with dengue fever.

Re:Won't Work

[Big Bob the Finder]

Just a stab in the dark, as I don't really have any special insight here. But it would seem likely the concept is to breed large quantities of GMO'd mosquitoes in the lab (providing them with the antibiotic throughout their life cycle), and then release them into the wild. They would then mate with wild-type skeeters, producing offspring with the gene. When those offspring fail to reach maturity because of the absence of tetracycline, it reduces the number of mosquitoes in the wild.

This is not exactly a new concept, although the implementation is quite different. Cattle screw worm (which was a serious economic pest) has been eliminated from North and South America from an aggressive irradiation program in which larvae are reared in large numbers, and then irradiated with cobalt-60. Insert your own "huge, radioactive flies" joke here, but the net upshot is that the irradiated flies mated with irradiated flies and failed to produce fertile offspring for whatever reason. Fewer fertile offspring is a good thing when it comes to population control of undesirable cattle parasites.

Similar programs with Mediterranean fruit flies have been used to control or eradicate populations, but there were some issues a few years back with making sure they really were sterilized by the procedure.

So, it's nothing *that* new, and variations on the technique have proven useful in the past. Now instead of green, glow-in-the-dark flies, we'll just have mutant, GMO'd mosquitoes. Life goes on- hopefully without dengue. Maybe someday without malaria.

flying needles

[tonyahn]

what will they come up with next? Maybe they can genetically alter the mosquitos to carry our flu shots.

The Eco-Nut replies are telling

[ZWithaPGGB]

Lots of people worried about birds or "The Ecosystem". Very few seem to be worried about the millions of PEOPLE who die HORRIBLE DEATHS thanks to Dengue fever.

I guess it's to be expected from the "Silent Spring" crowd, who refuse to acknowledge that the REAL effect of banning DDT has been millions of deaths from malaria, against a hypothetical doomsday scenario. Sound familiar?

Re:The Eco-Nut replies are telling

[Nemilar]

You're failing to take into account the big picture. People worry about the ecosystem because people are a part of the ecosystem. What affects one section of it, affects it all, including us.

It won't do people very good if, because we wipe out one creature, another creature dies out, and then another, and so on. It's called a food-chain, and an eco-system for this very reason.

Re:The Eco-Nut replies are telling

[Jah-Wren Ryel]

Lots of people worried about birds or "The Ecosystem". Very few seem to be worried about the millions of PEOPLE who die HORRIBLE DEATHS thanks to Dengue fever. People are part of the ecosystem too.

Fuck with "the ecosystem" and you risk secondary and tertiary effects that may produce dramatic changes for people too.

I guess it's to be expected from the "Silent Spring" crowd, who refuse to acknowledge that the REAL effect of banning DDT has been millions of deaths from malaria, against a hypothetical doomsday scenario. Sound familiar? Lol! PERFECT example of your own short-sightedness. DDT was banned because it was really fucking up PEOPLE - not the "ecosystem." It looks like DDT would be the lesser of two evils now. But are you so sure that these genetically modified mosquitoes are really the lesser of two evils? How do you know that? Are you so sure there aren't any other options?

Did you see that news article today about how partisan people are all about the emotional reaction rather than rational? Your use of term "Eco-Nut" and your simplistic framing of the discussion all point to a partisan opinion on your part.

Re:The Eco-Nut replies are telling

[jaxtherat]

Uhm, DDT was banned as it is a carcinogen, and not for the environmental impact. All Organochlorides were phased out on most developed countries for that reason.

http://www.pan-uk.org/pestnews/actives/ddt.htm

What we now use are mostly Organophosphate based pesticides (which are probably just as bad, but 'luckily' the metabolites are much harder to trace, so you can't get sued if your products poison an entire generation :roll eyes:).

http://en.wikipedia.org/wiki/Organophosphorous

Re:The Eco-Nut replies are telling

[locokamil]

I can offer a little bit of perspective on Dengue fever, because I had a particularly bad version that required me to be hospitalized. During my hospital stay, I needed several blood/plasma transfusions in order to compensate for all the internal haemorrhaging caused by the virus. All in all, I was debillitatingly ill for almost five months.

As serious as the illness was, there was never any risk of me dying: my family is well enough off that I received good medical care. But for every guy like me with the resources to get by in the event of catastrophic illness, there are about a thousand who die, coughing and bleeding, in the gutters. I really wish people in the west would think about these people before they dismiss potential solutions to epidemics for "environmental" reasons.

Re:The Eco-Nut replies are telling

[QuoteMstr]

What balance? How about the rise of oxygen-producing cyanobacteria, which single-handedly raised the concentration of oxygen to where it is today over a few million years? Keep in mind oxygen was a poison back then, and no doubt killed a lot of early life.

How about the Permian-Triassic mass extinction, which killed 96% of all marine species and a little over 70% of land species? How about the Cryogenian glaciation, also known as Snowball Earth, when glaciers reached the equator? How about the Carboniferous, when the oxygen concentration was so high that wet grass could burn? Hell, compared to the last ice age, the last ten thousand years have been wickedly hot and weird.

There is no balance in nature. There was no Garden of Eaden before we ate from the tree of science and sinned with industrialization. There was no paradise, only variable, capricious nature. The environment is valuable, but remember that we should protect it for our sake, so that we have a place to live, not because a trout or a tree is morally superior to man.

Re:Genetically Engineered Mosquitoes

[MichaelSmith]

release Love Bugs into our environment to breed with the mosquitoes and effectively make them sterile. Well, if anyone has ever been to Florida during the summer, then you know that not only are there an ass load of huge fucking mosquitoes but also a shit load of love bugs.

I am sure cane toads eat love bugs. I can get you a great deal on cane toads. They are priced per 100000 kilos

Mistake in subject....

[Schlopper]

"Engineered Mosquitoes Could Wipe Out Human Race"

There... fixed that for ya. Now queue overlord-welcoming comments....

The environment arguments are one-sided

[khallow]

The thing that annoys me about the concern over certain mosquito species (some which aren't native) is that this ignores that poor people have the heaviest environmental impact. I doubt even a disruption of the local food chain is comparable. And what's one of the many ways to make lots of poor people? Sick people. Sick people miss work and incur health costs. They often get permanent disabilities. And that adds up especially when 100 million people get sick each year. And everyone that dies is someone who could have contributed to raising themselves and others out of poverty. And in case people have forgotten why poor people contribute more to environment problems, keep in mind that poor people cause more environmental damage both through lack of education, apathy, and because the small economic gain from considerable environmental damage can pay for food and such things. Further, they have a higher reproduction rate than wealthier people.

While disruption of food chains are well known, the current argument seems to be that we don't "know" what effects the proposed strategy will have on the environment. As I see it, the effects of poverty and overpopulation are well understood while the effects of food chain disruptions are also well understood. What else is there? And more importantly, if one were rational about it, how would you rank the potential for environmental damage either way? What mitigating factors can you use? As I see it, the effects of poverty and the role of disease in perpetuating that are clearly harmful in an environmental sense. The effects of food chain disruption are pretty clear as well. Keep in mind that humans have been killing mosquitos wholesale for quite some time and disrupting food chains when they do so. Finally, there seems to be unfounded concerns about the modified mosquitos with no justification given for that. Name the danger, the unintended consequence not some vague concern because humans did some unrelated and that had unintended consequences.

Programmers' days numbered

[HalfFlat]

Programmers beware! You're next! This is only the tip of the iceburg:

Oxitec is also working on genetically modified versions of fruit flies, pink bollworms and coding moths.