Does the pandemic agreement make the world safer?

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Hello and welcome to the BBC Inside Science podcast, you lovely curious-minded listeners. This programme was first broadcast on the 22nd of May, 2025, and I'm Victoria Gill. Today we are immersing ourselves in the inner life of an old, famous tree. And I will be talking to Sesame Street's scientific advisor. Now there's a job title that makes me question my own career choices.

And as always, we have been combing through the hundreds of scientific studies and discoveries published this week that are shaping our view of the world. And Caroline Steele is with me to guide us through a few of the most fascinating highlights. Hi, Caroline. Hi, thanks for having me on again. It's always a pleasure.

What have you got for us this week? So I've got news that one side of the moon is hotter than the other, some positives of penguin poo, and what science says about the best way to chop an onion. Truly eclectic. I would expect nothing less. Back with you shortly.

Now, though, members of the World Health Organisation this week have agreed the text of what will be a legally binding treaty on tackling future pandemics. It's been described as a significant milestone in our shared journey towards a safer world. More than a year later than planned, the agreement is designed to avoid the inequity, disorganisation and competition for resources, including vaccines and personal protective equipment, that were seen during the COVID-19 outbreak.

So, does this treaty make the world a safer, fairer place? Andrew Green is a global health journalist and he spoke to us from the World Health Assembly in Geneva. So this has been an ongoing process for three years, in fact, just a little bit more than three years. And it emerged out of the COVID-19 pandemic. What happened is you had global officials at the WHO and elsewhere taking stock of... What was going wrong in that outbreak?

You know, countries weren't sharing information. Other countries weren't getting access to vaccines that were being developed or diagnostics or other forms of treatment. And they said, OK, we need to create some kind of agreement that would limit. these outcomes in the future, because obviously there are going to be future outbreaks. So thinking through how we can do a better job, how countries can come together and what they can commit to, to kind of...

prevent those same outcomes again in the future. What kind of outcomes were we talking about? You know, poorer countries not having access to and being able to afford vaccines, for example. So there being a sort of inequity in how the benefits from the science.

shed. Exactly. So there were questions at the very beginning about countries not reporting, either that COVID had emerged or the correct number of people who were sick with it. There were then questions about the recognition of and sharing of. the pathogens that were developing as the pandemic went on and the virus evolved. And then, of course, there was the big issue, particularly in countries of the global south, where they just weren't getting...

access to vaccines as quickly as the countries in the global north, the United States, countries in Europe. And so they were continuing to see people get sick and die, even as, you know, the United States and elsewhere, they're rolling out these massive vaccine campaigns. So what does this agreement commit countries to? What have they agreed? It kind of leaves out a set of...

principles and approaches that countries are committing themselves to. So they're saying, we're going to share information when we see potential outbreaks. We're going to commit to...

doing surveillance, to improving our surveillance system so that we can detect diseases sooner. We're going to share that information when it becomes available. But then also the key component is the pledge to... ensure that there's equitable access to any kind of treatments or vaccines that do develop in future pandemics so that, you know, people can get well faster or they can make sure that they don't get sick in the first place.

Sharing of scientific information, the genetic code of the pathogen, is that something that's still yet to be worked out, exactly how that information will be shared? The news out of Geneva has been a bit misleading. There was an agreement reached. But there's still an annex that needs to be negotiated over the next 12 months. And until that's done, then the treaty won't be open for signature. So it won't go into effect. And what still needs to be negotiated is these two issues. One is how...

The vaccines, information about vaccines, information about treatments is going to be equitably shared among countries and by pharmaceutical companies, for instance. But then there's also a question about. sharing of information about pathogens. So you've seen poorer countries kind of tie these two things together. They say if we're going to share pathogen outbreak information with you, then you have to make sure that we then get access to any vaccines, any treatments that emerge.

out of that information that we're sharing. You've seen a pushback then from countries in Europe who say, we're not sure exactly how that's going to work. So that still needs to be hammered out over the next 12 months.

Theoretically, when that annex is reached, then the treaty comes into effect. Now, there was a country that was notably missing, wasn't there? The US is not a part of this. What does that mean for the agreement's effectiveness? So the idea being that this is global, this is multi-level?

On the one hand, this is being touted as this big victory for multilateralism at a moment when you're seeing these unilateral tendencies. And it's worth noting that the negotiations really did speed up after the United States pulled out. Whether that means...

Washington was holding it back or it just means that people wanted to make a statement in support of multilateralism is up for debate. But then it does become a question of if you have this global superpower that's not committing to participate in.

the sharing of information that other countries are and also that houses a lot of the pharmaceutical industry that would be tasked with developing vaccines or treatments or diagnostics, then how effective is anything that these countries are binding themselves to going to actually be when they're lacking that necessary component.

What were the other sticking points then? Why have these negotiations been so delayed? There's kind of a big misinformation push at a certain point that the... treaty was going to rob countries of sovereignty, that the treaty, and again, this is not true, but there was rumors were being spread that the treaty would allow the WHO to do something like

enforce vaccine mandates or institute lockdowns in countries. Again, it does not. In fact, the treaty has no enforcement mechanisms. So even though it's theoretically legally binding, there's no way for the WHO to actually enforce anything that countries are agreeing to. Countries in the global south were also kind of concerned about what they were signing up to in terms of the financial commitment, because, you know, this does really come with some commitment to do surveillance, reporting.

And these are countries that don't have a lot of health resources. And so then this treaty is dictating that they need to be spent on these specific tasks. And then you see countries asking, well...

What about our other health priorities? Who's going to pay for that? That ultimately did kind of get smoothed out in the end. You did see the Global South come on board with the treaty, but there's still be some lingering questions about exactly who's going to pay for all of the obligations that the treaty introduces. Has this agreement made the world a safer place? Have we got to a point where we are more prepared for the next pandemic with this agreement? I think you can say yes. I mean...

definitely was a stock taking of what went wrong and the COVID-19 pandemic, you know, an effort both to identify that and then to introduce solutions to those problems. And so you have seen countries. Again, you know, the United States is not among them, but much of the rest of the world agree. We are going to commit to taking these steps. We are going to do everything we can to facilitate the quicker sharing of information, to facilitate faster response when we detect the disease.

That's no small thing. That's really incredible. Thank you to Andrew Green there. Have you ever wondered about the inner life of a tree?

Well to get under the boughs and beneath the bark, one historic tree in London has been given a digital twin. So why, in a park full of glorious real-life trees, would we want to explore a digital recreation? Inside Science's own Marnie Chesterton went to investigate. I'm at Royal Botanic Gardens Kew looking at a couple of trees. One of them is the Luscombe Oak. It's one of the oldest trees here at Kew.

And next to it is its digital twin. It's a new digital art commission. It's a 30-foot high plinth that shows an interactive digital version of this tree. throughout the course of a year, and it highlights a lot of the processes that are just normally invisible to us humans. To find out more, I'm off to meet one of the artists behind it. I'm Ersin Arasin. I'm an artist and director and part of London-based experiential artist collective Marshmallow Laser Feast.

So why have you built this? This is very beautiful, by the way. Congratulations. Thank you. Thanks for being here. As an artist collective, we seek to find emotional resonance in scientific stories and our kind of foray into the living world.

took us to meet some of the incredible oaks of the UK and that journey led us to the current project that you are standing beside which is called of the oak one of the main compounds is this large-scale outdoor video piece that is interactive that is looking at the hidden animism that is often tucked away and invisible to human eye and by visualizing these systems and networks to show how animate

tree can be. Let's talk through those networks. What have we got here on the screen that is normally invisible to us humans? You know, one part of it is the life-giving oxygen. So we take anywhere between 17 to 30,000 breads a day, a third of those coming from the trees. But we don't see that. We are in this intimate relationship with trees. thousands of times a day and we are yet to experience and explore this.

by visualising the oxygen that flows around the tree that you can also move around in front of the screen that reacts to you and makes the oxygen visible, allowing people to feel their agency but also interactively reveal that invisible bond. And the second part is we've gone through a number of different medical and architectural imaging techniques to visualize these inner systems. So I can say this is probably one of the most accurate representations.

a portrait of a real living tree which stands next to it. OK, well, this is a science programme, so I'm going to go and find the scientist who provided the data. I'm Dr Justin Bate, Senior Research Leader in Space Wellness here at Kew. So these hidden processes that this artwork is visualising, they're based on actual science, right?

Yeah, so we're actually using 3D scanners and the latest technology to record what's going on on the outside of the tree in really high detail, but also inside the tree. So we're actually looking below ground using radar to look at the roots and then the tree itself we're using LADAR. to actually look at the 3D structure. And this is your LiDAR machine? Yes, so this is one of our scanners. We use this kit for...

producing scans of the trees. What it allows us to do as scientists is actually take a tree and virtually take it apart in the computer. So we can break every single element of that tree up, look at the leaves, look at the individual branches. And at the simplest level, it gives us some idea of the weight of that tree and how much biome.

that's how much carbon is absorbing and because it's so accurate we can run that over several days or several years and see how much the tree is recording which parts of the trees are moving which is expanding which is shrinking

Essentially, if we just do a quick start now, all it's going to do is basically initialize itself so it's level, collecting lots of GPS readings, and then it starts scanning. So as it scans and spins around, you'll be collecting millions and millions of points, shooting a laser. getting a return from that laser which gives us the distance and the angle very similar to like a bat or echo sounding and that allows us to build a 3D picture in really high resolution.

Dr. Justin Mote there, ending that immersive report from Marnie Chesterton. Control your fragrance with the app, choose from clean, long-lasting scents, and enjoy sleek design that complements every ride. Right now, get 15% off Pura Car Pro and all-car fragrances, but only for a limited time. Visit Pura.com and upgrade your summer. drive today. You're listening to Inside Science on BBC Radio 4 with me Victoria Gill.

Now it was announced this week that a new season of the much-loved preschool TV programme Sesame Street is heading to Netflix. The series is in its 56th year, but it was facing an uncertain future after the entertainment giant Warner Brothers Discovery didn't renew its deal with the show. And President Donald Trump issued an executive order to block federal funding for public broadcasting in the UK. US, some of which has funded the production of Sesame Street.

The Netflix deal that has rescued Elmo, Big Bird, Cookie Monster et al. seemed the perfect opportunity for us to delve into the science behind a programme that sets out to nurture children's curiosity. I spoke to someone who plays a key role in helping Sesame Street...

get its science right. Sarah Sweetman is Associate Professor of Elementary and Environmental Education at the University of Rhode Island in the US. And before we hear from Sarah, here's one of the street's most famous residents. So Elmo, why do you need Sarah's help? Because today, Elmo wants to learn all the best scientists.

As a media advisor, there's a handful of roles that we play. So I help to write their STEM curriculum. And then once the shows get started, I review everything from a pitch of an episode idea, if there's animation.

animation or getting to be on set when it's being filmed if it's a particularly tricky science concept oh wow so you advise on set as well so what characters have been involved in your stories and how do you kind of interact with those characters and how those stories are told over the years have been advising sesame since 2009 and i have gotten to work with a lot of the characters we started with grover became super grover 2.0

of his new science and technology skills. He investigates. What does this button do? He was a really great character. Super Grover 2.0. He shows up. I guess you would think he was unlikely because a lot of people have a perception that science and engineers are very methodical and, you know, they have a plan and they stick to it and they follow it. And Super Grover was more the, I'm going to show up and I'm going to try something.

ideas out and see if they work. And I'm going to keep trying if they don't. And so he was a really great model to show kids that science isn't just wearing a lab coat and following a procedure. It's really about that inquiry. And it's about investigating and trying your ideas. That's the kind of essence of science, right? It's kind of reforming your question and experimenting and starting again. But science can be complicated. What would you say about the...

Challenges of breaking it down to a young audience, but also turning into working with these creators to turn it into those engaging stories. You have to bring these complex concepts to where they're at and connect it to something they already know. tricky. For example, we have done curriculum on the physics of the idea of a stronger wind can push something more, a light breeze will push something less.

That idea seems fairly basic, yet you need to understand that air is something. And most three- and four-year-olds envision... that there's nothing right air isn't they don't know yet that it's matter that it has mass and takes up space and so we have to help them gain experience and concepts with that before we're even able to get at the push and pull of wind okay now that you've observed and asked a question it's time to investigate investigate

Don't joke me. That doesn't sound like a real word. Investigate. It means looking closely and trying to find the answer to your question. You work as a researcher as well in a university campus. You can't specialise in every science. Do you go to any of your colleagues for help with specific stories and specific concepts? Yes, absolutely. I love working on a college campus for the expertise. that's around me, I will often call and say,

I know you're really busy, but I have a question. And the question is coming from Sesame Street to help make their show better. And it's amazing how quickly the scientists that I work with will stop what they're investigating to be able to spend time and answer. my questions. I think, you know, their own experience growing up on Sesame Street and that love that they have developed helps them to be able to prioritize the desire to help Sesame Street. No one can say no to.

To Sesame Street. Exactly. There's official advice about limiting screen time for very young children. So how do you kind of strike that balance? How do you think about that when you're working with the concept of a TV? program, being a medium for getting kids engaged with STEM and teaching children. How do you balance those two things? That's a great question. And I think it's a question a lot of parents and educators ask.

I would first like to say that not all media is created in the same way or with the same intent. What we know is that kids aren't passive when they're watching these shows. They are actively engaging with their brains. Sometimes they're physically...

enacting the show in their living room while they're watching. You know, I would encourage families with their kids watching Sesame Street to also go play Sesame Street. We have children's attention for eight minutes a day what in those eight minutes can we do to give the best possible learning experience i wouldn't have believed it i guess myself as a parent or as a teacher until i was in it

saw the passion of the educators that are working in the show. Do you have a favourite character or would you prefer not to be drawn on favouritism? Right, exactly. As an educator, we were taught, you know, never share your favourites. But I love when I see the teamwork across the characters. I really think their own personalities come out when they're working together. One of the episodes, Zoe and Elmo are trying to make Zoe's pet Rock Rocko float. Maybe, maybe Elmo and Zoe can make a boat.

Out of what's already here. And they're trying to design a boat that will make a rock float. That's a great idea, Elmo. You guys can be like engineers and design a boat. The science of it, the engineering was tricky. The rock was making... a lot of material sync. And those real-life persistence and investigations like that, that kids can then go do at home, episodes like that are really exciting. Who says he wants to try? Okay, then. Well, let's...

Fantastic. Well, Sarah Sweetman, thank you so much for sharing those stories with us from Sesame Street. Do give Supergrove a 2.0 inside sciences. Best regards. And Elmo. I will.

And Caroline Steele is still with me. Caroline, did you used to watch Sesame Street? I used to love Sesame Street as a kid. Yeah, it was one of my absolute favourites. And I have a really nice memory of a particular... episode I must have been about seven or eight at the time when I watched it and it was about Oscar the Grouch he's the kind of green bin bin dwelling character yeah

He had a pet worm for a bit. Do you remember his pet worm? I think so. Yeah, this rings a bell. So his pet worm really wanted to go to the moon and the pet worm joined the worm space program called WASA and ended up going to the moon.

moon and i remember that was the first time i'd ever heard about astronauts and for a kind of long period of time between like seven and twelve i really wanted to be an astronaut and i'm sure that played into it i sort of gave up on that idea when i realized i was claustrophobic but my love of space

stayed and I went on to study physics and astrophysics at university. Oh, how wonderful. So we can kind of thank Oscar the Grouch in Sesame Street for the fact that you're here talking about science today. Definitely, yeah. And I re-watched that episode. And it had a really nice message that sort of went over my head at the time. But it was very much like anyone can be an astronaut. It's not too big a dream for anyone, even for a worm.

That is lovely. But moving on, this week you have been scrutinising the journals for us, haven't you? So what are the stories we need to know about? So a recent paper published in Nature has reported that one side of the moon is hotter than the other. And I'm not just talking about the surface. I'm talking about underneath the surface of the moon. So the actual sort of insides of the moon.

So scientists have long known that one side of the moon looks really different from the other, right? So the side that we can see from here on Earth is sort of smooth. It has those darker patches from old lava flows, whereas the side that we can't see is sort of...

covered in all these little craters and it's not very smooth. So they look really different. And it's long been a question, why do they look so different? One theory has been that something different is going on underneath the surface on each side of the moon. But until... This paper, that's just been a theory. But data from NASA's GRAIL spacecraft finally have the data to back this theory up. So in the GRAIL mission, which happened in 2011 and 2012...

Two spacecraft called Ebb and Flow, which is quite cute, orbited the moon and collected data on how the moon's gravity affects them. Now, this is quite complicated because the moon's gravity changes with position. But it also changes with time because the moon pulls on Earth and gives us tides, right? Yeah. But those tides also pull back on the moon and change the moon's shape and change the moon's gravity. So its gravity shifts with the orbit. Exactly.

Exactly, yeah. So it changes with where you are and also what time it is based on what tides are going on on Earth. Right. And basically these spacecraft found that one side of the moon was deforming more in response to the pull from Earth than the other side, suggesting that it's 100 to 200 degrees Celsius warmer than the far side of the moon. So it's likely that...

underneath the surface of the Moon, on the side that's closest to us, it's sort of more liquid and malleable than the far side of the Moon. And this might explain why the two sides look so different. Ah, fascinating. But we still don't know, you know, a lot about...

these differences between the two sides. So the next step is scientists are going to study moon quakes, which are like earthquakes, but on the moon, and should give us even more information about what's going on. Oh, we'll keep a close eye on that. Thank you, Caroline. Now, moving on, I believe...

you have a story about penguin poo. Yes. So... According to a paper published in Nature Communications Earth and Environment, penguin poo may reduce the effects of climate change in Antarctica. My question is how? Good question. Antarctic ecosystems are struggling, right? We're significantly losing sea ice because of human-driven climate change, which is a problem for penguins, which really rely on the sea ice. Now, penguin guano, penguin poo, contains a lot of...

And ammonia can increase cloud formation because ammonia reacts with gases in the air. to produce aerosols, which are basically tiny particles that water vapour can condense onto and form clouds. So more penguins means more penguin poo, means more ammonia, means more aerosols. means more clouds and clouds cool the local environment because they're white and reflective and they reflect sunlight back into space and keep the area underneath the clouds cooler. So scientists wanted to know sort of...

how much of an effect this penguin poo is really having on the local environment. So they set up some equipment eight kilometres downwind of a 60,000 individual penguin colony and found that the ammonia in the air... increased by a thousand times higher than the baseline value because of this penguin colony. And even when the penguins moved on...

there was still 100 times more ammonia in the air than normal because of the penguin poo still releasing. So it's having a huge effect. And they also managed to match that up with increased cloud coverage as well. More reason to love penguins.

We didn't have enough. Now, I feel like we're sort of zooming in from the solar system to Antarctica to the kitchen because there's a chopping board in front of me, which I believe has something to do with you and the last story that you want to share with us. What is this for?

cry when you chop onions when you're cooking. I mean, the quick answer is yes, but I've got to admit I don't do most of the cooking in my house. So you avoid the onion chopping. That's one way of dealing with it. I deal with it by wearing goggles. I actually have a pair of swimming goggles in my kitchen. Swimming goggles. Yeah, yeah. This is predictably...

Scientific of you, Caroline. I love this. And that does the job. But, you know, understandably, not everyone wants to wear goggles when they chop onions. Physicists at Cornell University in New York may have found a solution to stop you from crying when you chop onions. OK. onions, they spray a mixture of sulphur-rich compounds into the air, one of which is synpropanethyl S-oxide, and that's the one that basically irritates your nerves in your eye, which produce tears.

And what these scientists did is they used a high-speed camera to analyse in detail the spray that's produced when the onions are cut with... Blades of varying degrees of sharpness, so really sharp blades, really blunt blades, and at varying speeds. So sharper blades produce fewer, slower droplets with less energy, whereas if you cut an onion with a dull blade, the particles...

can reach up to 90 miles an hour and there are 40 times as many droplets as when you use a sharp one. And the reason for that is basically when you push down on the onion when you're cutting it, it builds up all this elastic potential energy, all the liquid in there ends up

at a really high pressure and if you're pushing down on it sort of for longer before you break the skin with a blunt knife, suddenly all this pressure is released and it creates these incredibly fast droplets that end up in your eyes. That makes sense. And interestingly... If you chop an onion at a faster speed rather than a slower speed, you produce four times as many particles. So you want a sharper knife at a slower speed.

But the physicists didn't actually test the crying part, so I thought we could do that now. We could finish off the research. So just bear with me whilst I remove the skin. Right, so I'm going to cut using this sharper knife. At a slower speed. That's a slow chop. I'll put my eyes right by it. No swimming goggles. Oh, wow. This is fine. Really? Yeah, genuinely. For listeners, Caroline does have her eyes.

About four centimetres away from that chop, don't you? So that seems to work, right? So a sharper knife, slower speed. Right. Our eyes are doing well. Right. So now we've got a blunt knife. I'm going to try to chop it faster and see what happens. Swift chop. Oh my gosh, my eyes are already going. Really? Basically, our mini experiment in the studio supports the findings, right? Faster knife, slower speed, fewer tears.

Blunter knife, faster speed. My eyes are burning. Luckily, I don't need to read the last bit of script for this programme. So I'm done. Caroline Steele, you are just an absolute soldier. Thank you very much indeed.

And that is all we have time for this week. You have been listening to BBC Inside Science with me, Victoria Gill. The producers were Jonathan Blackwell, Dan Welsh and Claire Salisbury. Technical production was by Kath McGee and the show was made in Cardiff by BBC Wales and West. Marnie Chesterton will be taking on the most pressing listeners' scientific questions. So until then, thanks for listening and bye-bye.