Could Mosquitoes Actually Cure This Disease?

Could Mosquitoes Actually Cure This Disease?

For half of the planet, mosquitoes are more
than just a nuisance. Their bites transmit parasites and viruses
that kill millions of people each year. One of them, dengue virus,
causes dengue fever. It’s often called breakbone fever because the patients feel like the bones
in their bodies are being broken. If you get sick with dengue, you can have
mild symptoms through to very extreme symptoms, where you’re going to have internal bleeding, shock and can die. So it’s a big spectrum but if you speak to anybody that’s had
a bad dose of dengue, they’ll tell you it’s one of the worst things
that happened to them in their life. Dengue is considered the world’s fastest
spreading tropical disease. Its cases have risen thirtyfold in the last 50 years. Dengue is like everywhere in the tropics. Potentially 40% of the world’s population
is at risk this year of getting dengue. That’s a big number. We’re talking about billions of people. And with the world’s temperatures rising, dengue can spread out of the tropics potentially
reaching a further two billion people by 2080. In Indonesia the total number of dengue cases
is second in the world. It has been proven very difficult to sort of get rid of all the mosquitoes causing dengue. In the laboratories chemicals are discovered
for killing mosquitoes. We’ve tried very hard but still,
the mosquitoes are around us. So it needs something else to combat dengue. Eight years ago Scott O’Neill founded The
World Mosquito Program, a non-profit initiative running trials in
12 countries around the world, one of them here in Indonesia. Their sole aim is to eradicate dengue. In particular one mosquito, Aedes aegypti, it is responsible for transmitting between
people a number of diseases. Some of them obscure, some of them quite famous. So diseases like yellow fever, dengue, chikungunya,
and most recently, Zika. And the reason that this particular mosquito,
Aedes aegypti, is so good at being able to cause these explosive epidemics is because it’s like the cockroach of the
mosquito world. Just like cockroaches,
it likes to live with people. It doesn’t live out in the forest in harmony
with nature or whatever, it lives in people’s houses, in concrete jungles, in cities, and it bites people, maybe two or three times a day. And so often whole families get sick with dengue, because that one mosquito bit everybody in
that house within a period of a couple of days. As soon as people discovered
that mosquitoes transmit disease, the immediate response is let’s kill mosquitoes. The thing is all those diseases are still
pretty well here. And the reason is that
mosquitoes are really tough to kill and if you realize where they breed,
you know just in a tiny bit of water, you realize that there are millions and millions
of places where these mosquitoes are breeding and a thought of killing
every single one of them just seems impossible. Most researchers have focused on genetically
modifying mosquitoes, or trying to eradicate the species entirely. Instead, O’Neill’s team is infecting mosquitoes
with bacteria – not to kill them, but to inoculate them. It’s a naturally occurring bacterium called Wolbachia. That bacterium spreads into the mosquito population, and once the mosquitoes have it, they’re
unable to transmit the virus between people. You know, I’ve had this obsession for a long time
of working on Wolbachia. It occurs naturally in around 60 to 70% of
all insect species all around the world so wherever you live, if you were to go outside,
grab some insects out of the nearest bush you’d likely find, more often than not,
that those insects naturally have this bacteria called Wolbachia. The mosquito though, that transmits all these
viruses to people, doesn’t have it. When we were able to put the Wolbachia
into the mosquito and then we fed those mosquitoes in a laboratory virus, we found that just Wolbachia by itself,
without any fancy tricks, would stop the transmission of the viruses. Wolbachia was stopping, not just dengue, but
yellow fever, chikungunya, Zika, Mayaro, a whole range of viruses and so it was a major discovery. But introducing Wolbachia bacteria to disease carrying mosquitoes like the Aedes
aegypti isn’t easy. In fact, the only way to do it is to inject
freshly laid mosquito eggs with the bacterium. This process takes time. O’Neill’s team has spent more than five years
building their colony of a few thousand mosquitoes. But that was the hard part. Now, nature takes over. This bacterium transmits itself vertically
from a mother to her offspring, so it gets carried in the egg. So what Wolbachia does is that if it’s in
a female it will be transmitted and so that female can mate with either males
that have Wolbachia, or males that don’t and she’ll produce eggs, and those eggs
will all have Wolbachia. The trick though is the other way. If the male has Wolbachia, but the female doesn’t
have Wolbachia, then she will lay eggs and all her eggs will die. The end result of that is that only females
that have Wolbachia are able to reproduce. And so Wolbachia then spreads into the insect population without having to be infectious, without having to jump from one individual to another. In Yogyakarta, whenever you go to the community
and you ask, ”Do you know anyone that had dengue before?” my guess is that everyone will answer “Yes.” Because it’s so common, and it’s still created
a panic within the community. People often, who live in transmission areas,
live with a lot of fear about dengue. Actually it’s a family of viruses.
It can be grouped into four groups. And unimaginatively, they’re called dengue 1, 2, 3, and 4. When you get infected, say, with dengue 1,
your body makes antibodies against dengue 1, and so it’s much harder for you to then acquire
dengue 1 again, the second time. But those antibodies don’t protect you for
dengue 2, 3, or 4. But not only that, those antibodies will
make it easier for dengue 2, 3, and 4 to get into your body and cause disease and
actually create potentially more severe disease. And so it’s possible that
you could get dengue four times. And each time you get it, you could potentially
become more sick and at greater risk of dying. Yogyakarta is where the group is conducting
a major study. They’re collecting data on how successful
Wolbachia is in stopping dengue transmissions. The first batch of mosquitoes
was released here in 2014. We worked with the community far before we
released the mosquitoes to make sure that they understand that what
we are targeting is the virus, not just the mosquitoes. This project would not have been possible
without the community understanding. Because the idea was like a controversy. Let’s think about it for a minute. We’re going to come in, a bunch of scientists and we’re going to release mosquitoes
into the community. And these mosquitoes are going to bite you. And all you’ve heard for the last 50 years
of your life is that you have to kill mosquitoes, because they’re dangerous. You would imagine the community
would be very cautious. I’d be cautious or I’d wanna know a lot
about what’s going on. And I think community is like that, and we understand
that, and we’ve really tried to address that. And by doing that, we’ve had virtually no opposition. Communities are a huge part of the project
and the team spends time explaining the science behind their intervention. But they’re also involving them
in the mosquito releases. People take in the buckets with mosquito eggs
and take care of them until the eggs hatch. In this space mosquitoes are being grown
that contain Wolbachia. So that we can collect eggs off them and then those eggs will be distributed into the community. In Yogyakarta we’re using human volunteers for feeding. Some of the researchers have been bitten probably more than a million times by mosquitoes with Wolbachia. All for the sake of disease prevention. The team keeps monitoring how many mosquitoes
in the wild have Wolbachia, and continues to release them until they reach
a certain threshold. Once this is done, the bacteria sustain themselves
in the mosquito population and the method doesn’t have to be repeated. Current data shows around 70%
reduction in dengue cases in the areas where Wolbachia mosquitoes
were released. But we think it’s a big underestimate, because
if you spend a little bit of time in Yogyakarta, you’ll notice that everybody’s on motorbikes
traveling everywhere. And so it’s possible that they’ve gone out, been bitten by a mosquito and then come back in and then get counted as in the intervention area. And it looks like, you know, everything that we’ve seen in the laboratory, our mathematical modeling, everything is coming together to suggest that
we’re gonna have a big impact on disease. By the end of this year the team’s Wolbachia
method will cover about three million people around the world. But they want to reach at least 100 million by 2023. The ambition for our program is big, but the
problem is huge. Eliminating diseases is very challenging. I think if you look at polio today, you can bring
polio down to very low levels. But to do the final elimination, so there
is no more cases, very challenging. Smallpox is an example, there aren’t too many others out there. Spreading Wolbachia mosquitoes around half
of the planet is a monumental task. It would require a huge injection of funding
and a coordinated effort of governments. But the three billion people at risk of such dangerous
viruses motivates the team to keep fighting. There’s an obsessive nature to the work that we do. And I think that sits behind a lot of science,
to have an idea and then to really hold onto it and then work and work and work and work,
until we’re successful. And so my hope would be that we could eliminate
dengue at some point.

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About the Author: Oren Garnes


  1. Big thank you to the researchers, especially the ones that allow themselves to be bitten for science. There isn't a lot of money in this. These ppl are heroes!

  2. Canbig thanks to the research team you made a big impact to our world specially those communities that needed your intervention.. Keep up the Good work????????

  3. I have been affected with dengue 1.5 year ago and 0:37 is absolutely true . I felt like killing myself every single day because it was too much to handle.

    It destroyed my stomach functioning to the point where I don't feel either hungry or full anymore. Everything I eat is directly vomited out. I got multiple tests done on my stomach just to make sure that there's no internal bleeding everyday. Next, it affected my liver and almost started destroying it (blood results showed starting stages of jaundice). All these days I was hospitalized and only drinking some juices , eating very little food . Was connected to IV fluids 24×7 and had to get my blood checked thrice a day – meaning 3 needles a day in your arms 🙂

    It became so worse to the point where doctor was thinking about giving me blood transfusions everyday but my body miraculously showed signs of recovery on the very last day. You know the crazy part? You lose all of your body strength to a point where you feel dengue after effects on your body for 1-2 months minimum.

    Only people who are affected with dengue will understand why it's so fucking dangerous.

  4. there are 4 strains of dengue I suffered from dengue 2 times. Now i am immune to 2 strains. The symptoms are high fever that cannot be controlled by paracetamol followed by drop-in platelets count. My platelets went down to 15000 (normal >150000) The drop in platelets means your resistance to other diseases is low and if you catch a secondary infection it can be deadly.

  5. super awesome work! I don't understand why it would take so much money though. seems like they just need to send larvae to different countries. maybe the issue is that this species they are working on only lives in certain areas so they would need to modify other species to accept wolbachii

  6. I'm still up for exterminating mosquitoes, we are so good at exterminating other species that are not harmful to humans, we should really try to eradicate mosquitoes, I'm sure we could succeed if we put our minds to it

  7. I guess thats another reason why i’ll live in cold countries, fuck that I love canada now lmfao, we also don’t have very dangerous animals or ticks etc

  8. Nice job! Just some of my thoughts… Breed an insane amount of creatures that eat mosquitoes, which will have the least environmental and social impact. There has to be smells or sounds they cannot stand. Many people who are not used to those environments go there on a vacation and they take it back home to many countries around the world.

  9. If you can't beat them, join them, or in this case, make them join you. Incredibly smart way to beat the animal that kills more humans than any other one. It's kind of crazy that this works!

  10. This guy is helping the human population to grow faster, this will eventually lead to the human extinction. Once we grow to 20 billion people we will start ww3 and nuke ourselves. We need environmental factors that are preventing us to grow too fast.

  11. The human population must be reduced, this is the only way to save humanity from extinction. Global warming is made by humans, if diseases spread faster due to this and killing humans then this is great news, because reducing the human population is preventing global warming. Kill idiots like this to save humanity.

  12. I Think we need to fund more for this Organization… It's for the sake for Humanity… anyone wanna to join? We need to stop this cursed disease…! We have so many problems that happening to our earth… start from climate change which made this situation worse… Maybe i can contact the Organization and ask can we fund them…

  13. Why many people died is because they were late in getting treatment. It can be treated easily. Usually they thought it was just a viral fever and just pop paracetamol untill it was just too late.

  14. school is so amazing that ive literally never heard of this before! crazy i have to youtube it myself to see what it is lol thanks education system

  15. We should start with this in regions, that arent infectet wit dengue yet. you can start spreading the bacteria at a slower pace and have it multiply by itselfe, to prevent the virus before it arrives

  16. Can someone tell me the downside?
    These sort of miraculous inventions get talked about much before they actually become practical, and some of them don't even make it. Is there such a caveat here?

  17. In Thailand one TV star, have dengue for the second time, it was so severe that he have to amputate his limps and ended up lost his life eventually.

    Me I have dengue once when there was epidemic in Thailand, 15 years ago. Me and my sister got it at a very same month.
    I hope I don't get the second time.

  18. If the government really want to eliminate a certain disease they can. But why help people get cured when you want to eradicate human population to save the world.

  19. I'm from Sri Lanka
    and Dengue kills thousands of people every year in Sri Lanka and It's really sad to see specially little kids dying because of this. Still no proper cure.

  20. Dengue used to be common in the Philippines during the rainy season. But in recent years it's quite common all year round.

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