Introducing Mosquitos Infected with Bacterium Reduced Dengue Fever Cases By 75%

Last year nearly 400 million people experienced Dengue fever, according to All Things Considered. (Just Brazil alone had more than 2 million cases.) But The World Mosquito Project is trying an interesting solution: Scientists are cultivating and releasing mosquitoes, except these mosquitoes are special: They've been infected with a bacterium called Wolbachia. Wolbachia occurs naturally in many insects, but not normally in Aedes aegypti mosquitoes, which spread dengue. It has to be introduced into the mosquitoes in the lab. But then the bacterium is passed down to future generations. The bacterium appears to block Aedes aegypti from transmitting arboviruses, which include dengue as well as chikungunya, yellow fever and Zika...

"In Indonesia, we've [released Wolbachia-infected mosquitoes in] a community of 50,000 people and compared it to a community that was left without Wolbachia," says Cameron Simmons, director of the impact assessment team for the World Mosquito Program. "We've seen a 75% reduction [of dengue cases] over the last 2 1/2 years in the Wolbachia-treated community...." The problem in the real world is that other people and other mosquitoes keep migrating into the areas being treated, messing up the experiments. But from a theoretical perspective Simmons sees Wolbachia as potentially a way to wipe out dengue entirely.

"If you had a big island," he proposes, "[and] you stop people from moving in and out of that island, and you put Wolbachia across all the mosquitoes on that island, the science suggests that you'll eliminate dengue in that location."

Some countries are trying to do just that. Australia started using Wolbachia-infected mosquitoes nearly a decade ago to control outbreaks of imported dengue in the state of Queensland. This year the government of Malaysia launched a campaign called "Wolbachia Malaysia" to attack dengue.

They've been infected with a bacterium

[nospam007]

That's sick.
Literally.

Hmm...

[Mensock]

Aren't doctors concerned about "super bugs" that could be resistant to antibiotics?

Re:

[AHuxley]

The patient survives in a Dengue fever area to be billed another day for all kinds of other medical care.
Think of how much that longer a person who got past Dengue fever can now spend on medical care.
Middle age and lifestyle medical problems.
Health care well into old age.
Once Dengue fever would have reduced all that later access to health care.
Will less Dengue fever, more people are wondering around in the community to look after.
Billable hours go up with more people working needing decades of care wi

Re:

[jezwel]

Aren't doctors concerned about "super bugs" that could be resistant to antibiotics?

This would become apparent pretty quickly with fast breeding mosquitoes.

Some countries are trying to do just that. Australia started using Wolbachia-infected mosquitoes nearly a decade ago to control outbreaks of imported dengue in the state of Queensland.

Which you'd think would have been reported by now.

Re:

[sysrammer]

...Australia started using Wolbachia-infected mosquitoes nearly a decade ago to control outbreaks of imported dengue in the state of Queensland.

Which you'd think would have been reported by now.

You'd think, but not sexy enough, I guess. I found this...

[After 8 years]
"North Queensland is now essentially a dengue-free area for the first time in well over 100 years."

Dr Richard Gair
Director and Public Health Physician, Tropical Public Health Services, Cairns
https://www.worldmosquitoprogr... [worldmosquitoprogram.org]

...and the bacterium appears to have taken well into the population of skeeters.

Not so fast

[darthsilun]

Last year nearly 400 million people experienced Dengue fever,

But WHO says[1]: One modelling estimate indicates 390 million dengue virus infections per year .., of which 96 million ... manifest clinically...

Now, if "manifest clinically" means what I think it means, then actually less than 100M "experienced" it last year.

Because otherwise if 400M people "experienced" it, that's about 1 in 20 people. One person in our office in Bangalore has contracted it in the last several years and was hospitalized, but given the size of our office, we'd have seen a lot more than just one It's anecdotal to be sure, but still.

[1] https://www.who.int/news-room/... [who.int]

Fucking kill them all!

[mveloso]

Yes! The mosquito genocide has begun!

Oh wait, they're not being killed, they're being inoculated. Dammit!

Re:Fucking kill them all!

[proton_pump]

Truly killing all mosquitos will do much more harm than good. There are thousands of species of mosquitos out there, yet only a few species serve as vectors for human diseases such as dengue fever and malaria. Targeting just those specific species would be challenging but I think we could do it, however it is important to remember that the vast majority of mosquito species fill a valuable ecological niche -- they are pollinators and a major food source for hundreds of other animals -- so we have to be careful when we talk about killing all of the mosquitos because we don't want to do that, we just want to kill a few species.

Re:

[vovin]

Knee jerk food web bunk being regurgitated from kindergarten.
There is no need for mosquitoes in the food web as there is no species even marginally dependent on mosquitoes as a food source.

Re: Fucking kill them all!

[crobarcro]

Another person think's they're smarter than evolution

Re:"Knee jerk food web bunk"

[proton_pump]

There is plenty of a need for mosquitos in the food web, I really don't see how that could be disputed and it's not hard to see. First of all, there are many species of birds who eat mosquitos, not only when they are in the air but when they are in their larval stages in the water. Mosquitos are at the very bottom of many food webs, and thus are consumed by a variety of species. While there aren't any birds who exclusively eat mosquitos, they still serve as a direct food source to many. Furthermore, mosqui

Re:

[vovin]

Counter example: Hawaii
Hawaii was mosquito free until recent history and had a perfectly viable food web.
Not one single species is *dependent* on mosquitoes for food, hence they are not an essential part of the food web.

Ex: https://en.wikipedia.org/wiki/... [wikipedia.org]

Gambusia typically eat zooplankton, beetles, mayflies, caddisflies, mites, and other invertebrates; mosquito larvae make up only a small portion of their diet.

Re:

[proton_pump]

Okay all I'm saying is that mosquitos are a part of the food web and removing that could potentially have consequences, and I read that too about Gambusia, however I also read about how Gambusia caused issues because they out-competed other species for mosquito larvae and that in turn had negative consequences. I will admit while mosquitos aren't as large of a part of the food web as I once thought, they do participate in it and I do think that there are plenty of areas where the food web could be harmed if

Not just dengue

[rossdee]

as far as I know the aegypti mosquito also spreads other diseases for example west Nile.
I don't know if the bacteria treatment stops these other diseases, Malaria is still a big problem in some countries.
With climate change making the mosquito season longer, we need to make an effort to wuipe out all mosquitoes that bite humans.

There was only ever one good type of mosquito. They were made of wood by de Havilland and had a Merlin engine in each wing.

Re:

[sysrammer]

633 Squadron FTW!

natural selection

[dhammabum]

As is usual with natural selection, if there are 75% less dengue fever infections, 25% are still active. With that large of a active viral population, it would be surprising if the dengue (or other mosquito-bourne) viruses don't evolve defensive measures to counter the Wolbachia bacteria inhibition of virus transmission. Should happen in just a relatively few viral generations.

Very widespread and frequent distributions to try to capture the entire mosquito/viral population in an area should counter this ef

Re: natural selection

[dpille]

I doubt that's the case for dengue. The mosquito is merely the vector, not the reservoir, so there are easily trillions of times more copies of the virus that never see the inside of a mosquito than those that do. They'd be much more likely to evolve a solution to human immunology than a particular bacteria in some of the mosquitos present. I'm not sure you're qualitatively arguing anything different than "Dengue would just evolve to cause the mosquitos to be resistant to your insecticide."

Re:

[dhammabum]

Yes, mosquitoes are only the vector. The reason for the Wolbachia effect appears to be that infected A. aegypti females don't live long enough for the viri to develop sufficiently for transmission (DOI: 10.1126/science.1165326). I believe there are two evolutionary factors here. For the virus, over time, there will be pressure to speed up development. For the mosquito, which has not been exposed to Wolbachia in nature, there is pressure to adapt to the Wolbachia so the females can live longer and produce mo

Not good news for some people

[hAckz0r]

For the viral diseases, this may be good news. But for those suffering from the filarial diseases, this will only make their problems that much worse. The filarial nematodes (e.g Lymphatic filariasis, Dirofilaria, etc) are dependant on Wolbachia for creating their prodigy, and without them they become sterile. Since there is no "cure" for these filarial diseases one of the best options to improve the persons overall health is to kill the Wolbachia, which then reduces the number of microfilariae and other

Re:

[dhammabum]

Many, many arthropods carry Wolbachia. According to wikipedia, it is " one of the most common parasitic microbes and is possibly the most common reproductive parasite in the biosphere" (https://en.wikipedia.org/wiki/Wolbachia). I don't see how one more species will make a significant difference.

another use for infected mosquitoes

[NikeHerc]

Somebody please figure out how to create a mosquito bacteria that will prevent lunatic democrats from infecting our capitalist society with socialism!

Maybe mosquitoes, biting flies, parasitic worms,

[mark_reh]

and leeches could be used to deliver vaccinations, especially to populations who resist vaccination.

Load swarms of bugs up with whatever payload you want, then release them near population centers.