HPV vaccine uptake wanes, and boozeless beer health concerns
PodcastsThe Naked ScientistsHPV vaccine uptake wanes, and boozeless beer health concernsPlus, how the African landscape shaped early human development20 June 2025In this edition of The Naked Scientists: HPV. . .
PodcastsThe Naked ScientistsHPV vaccine uptake wanes, and boozeless beer health concernsPlus, how the African landscape shaped early human development20 June 2025In this edition of The Naked Scientists: HPV vaccination rates are waning. We examine the importance of the jab. Also ahead: why Africa is key to understanding the evolution of early humans. Plus, the reasons alcohol-free booze might actually not be all that good for us. . . HPV vaccine uptake is falling worldwideMargaret Stanley, University of CambridgeDoctors around the world are raising concerns about falling vaccination rates for the Human Papillomavirus, or HPV - the viral infection that causes cervical cancer. The HPV vaccine is typically offered to adolescents in school and has been a massive public health success story, cutting cervical cancer rates by up to 99% in countries with high uptake. But recent data from Scotland, echoed in other countries, shows a worrying decline in vaccination rates, particularly among young people in more deprived communities. Public health officials warn that this could reverse the earlier gains and undermine efforts to eliminate cervical cancer as a global health threat. Margaret Stanley is Emeritus Professor of Epithelial Biology at the University of Cambridge; she’s an internationally recognised expert on HPV and cervical cancer prevention, and helped to develop the cervical cancer vaccine we now use…Margaret - HPV vaccine was introduced in the UK in 2008. The Scots evaluated its impact over the 10 years of vaccination up to about 2020. What they found was in the 13 year olds who had received the full vaccine dosage, when they arrived for their first smear at the age of 25, there were no invasive cancers. Let me put that in context. The highest number of invasive cervical cancers, the real thing that kills you is in the 25 to 35 age group. And so the fact that this group was showing such a massive reduction, I tell you, this is a real public health triumph. HPV causes 5% of all cancers globally. Now, across the world, where you've had high coverage of this vaccine, 80 to 90% of girls immunised, then you've had reductions in cancer. If the coverage drops, then that possibly will disappear. Chris - What sorts of rates are we now seeing then? And what sorts of rates of vaccine uptake were we seeing?Margaret - Scotland before COVID had 90 to 92% coverage of girls. And the boys were coming in and they were getting high coverage too. Since the lockdown and COVID, when the schools closed and therefore the programme was tremendously effected, then it's dropped to about 65%, 70%. In some parts of the country, you're looking at 40%. Chris - Why in the particular groups that we're seeing this drop though? Because specifically, it's not across the board, is it? It's certain communities where the uptake appears to have really plummeted. So why is that? And is there anything that can be done about that?Margaret - This is a sexually transmitted infection. And particular religious groups, Islamic, Orthodox Jews, Orthodox Catholics, they are reluctant because they're worried about the sexual transmission and the possibility that this will make the teens more promiscuous. Although I have to say all the evidence says that's rubbish, that it doesn't change their behaviour. And then COVID did all sorts of dreadful damage. And one of the damage was to the trust that people have in medicine and in science. And so they're a significant tranche of the population, which is very uncertain about the benefits of a vaccine you're delivering to a 13-year-old. For a disease, they're not going to get until they're 30, 35. Chris - Are you expecting then, off the back of this, to see in subsequent years, a resurgence of cervical cancer cases from a near suppression to zero to cases emerging again?Margaret - I hope not. We've tried to fireproof the programme in the UK as much as possible, because we immunise boys. So the transmission between the two sexes is blocked. So because we've fireproofed it, I'm hoping that we won't see significant failure to fall. Humanity's road to dominance began earlier than expectedAndrea Manica, University of CambridgeFor a long time, the story of human evolution has focused on the moment our human ancestors left Africa, around 50,000 years ago, to spread across the globe. But why only then? Why not before? Well now a new study published in Nature reveals that - from around 70,000 years ago - early humans began to adapt to dramatically different environments across the continent, becoming much better at existing in more extreme conditions. This time period is also reflected in a change in the appearance of these ancestors: they all began to look a lot more alike, evidence, Andrea Manica, professor of evolutionary ecology at the University of Cambridge, argues of the population of Africa interacting a lot more closely, and likely sharing survival tactics in the process…Andrea - There is a really interesting puzzle in our origins which is we all derive from a group of people that came out of Africa about 50,000 years ago, and yet what we know is that people tried to come out of Africa many times before, and yet they left no trace. Chris - Well, if they left no trace, how do you know they did that?Andrea - Well, they left no trace in our genes, in the people that are here contemporarily, but actually there are lots of archaeological evidence, archaeological sites that show us that they were there before. Chris - In essence then, they tried and failed. Andrea - Yes, they somehow didn't manage it. Chris - The question then becomes, well, when it did happen, why then?Andrea - Well, that was our big question now, and what we see is that 70,000 years ago, suddenly people changed the way they're using their environment. They really start using the most extreme environments. They somehow learn how to cope with the deepest forests, the driest deserts, and they really manage to do things that they couldn't do before. Chris - Is that what has emerged from this study? Your argumentation is that something switched and we suddenly unlocked our potential. We became much better at coping with the exigencies of the environment we find ourselves in, and that opened the door to the rest of the world from Africa. Andrea - Yes, that was the moment when we became, in a way, the ultimate generalist that could really cope with lots of challenges. Chris - How have you arrived at that conclusion, first and foremost?Andrea - Well, what we did was actually to really focus on Africa, because what people had done before was more to think about what might have happened after their exit, whereas we really want to look at what people were doing before they came out. And so what we did was actually to work with archaeologists, and we put together information about every single archaeological site in Africa, the dates, and therefore we knew where people were, and then we linked those with reconstructions in climate. That's kind of using the climate models that people used to predict climate change, but used backwards. And so at that point we could actually say where people lived, but also what kind of conditions they lived in. And that's what allows us to see that actually suddenly, 70,000 years ago, they were using the kind of environments that before they couldn't really handle. Chris - But you've turned one question into another, which is, well why did they suddenly find themselves able to do that?Andrea - Absolutely. And we can't be completely sure of it, but we do have an idea, which is there is nothing special in the archaeological record at that time that suggests there was a magic invention in that particular instance. In a way that makes sense, because they're suddenly tackling very different environments. They're tackling wet places and dry places all at the same time. But there is one interesting cue that gives us an idea of what might be happening, which is that 70,000 years ago is also when we see the anatomy of humans across the whole continent becoming much more similar. So what we think is the moment when people are interacting much more, moving much more, much more in contact. And that contact, in a way, made everyone a bit more similar. But it also meant that, in a way, they probably exchanged ideas. Ideas were moving, ideas were created, and they were kept and exchanged. And that probably gave them the ability to suddenly deal with very, very different challenges. Chris - You don't think that that happens to also coincide with the emergence of languages or something like that, do you? Because if you've got that sudden dramatic ability to do what must amount to the exchange of information and knowledge and to pass that on, language would be a really good catalyst for that. Or do we think language evolved many, many years before that?Andrea - It's very difficult to say because, in a way, there is nothing left about languages. What we know, in terms, obviously, what they were speaking, what we know is that, in a way, symbolic art, so when people start thinking much more in an abstract way, actually happens earlier than that. So we don't think that there is a major, in a way, change in the way the brain was working at that particular point. So we think that probably that was already around, but 70,000 years ago is when people are interacting enough to really take advantage of something like language, that kind of cultural ability to build ideas and, in a way, build ideas upon ideas and therefore come up with something that is better than the sum of the individual parts. Chris - Now we're talking here about anatomically modern humans, us, our ancestors, but if one looks at our origins, we come from an ancestor that gave rise to us and Neanderthals. Neanderthals were around until 40,000 years ago or so, they were very like us, they probably merged into our population, but when did they leave Africa then? Were they also part of this exodus at 70,000 years or had they already left Africa?Andrea - So they've actually left Africa much earlier than that, we're thinking probably 350 or even up to 450,000 years ago. So they were, in a way, one of those first expansions of the ancestors of us and Neanderthal that made it into Eurasia and they, in a way, became the specialists in the cold climates. And it might even be the explanation of why the later waves didn't really make it for modern humans because. . . Chris - Well, that was going to be my question, which is, well, if they can do it, why the hell couldn't we? What was the hold-up for us that they, in some way, surmounted?Andrea - Well, we could do it as well, it's just that we were a species that was much more specialised in hotter climates and they were the really cold-weather specialists. And so when people came out of Africa later on, they were basically not really equipped for the kind of challenges that you had in Eurasia. There was actually a third cousin, as a matter of fact, that we had contend with, because in Asia there was probably Denisovans that we know very little of. And again, they would have been probably quite able to cope with a number of the cooler environments that you find in Asia. And they were probably a barrier for us. So what we see is that us, anatomically modern humans, came out at the good times when the weather was particularly good and then we always faded when the weather got worse. And those specialists were just there in a way and they pushed us back. Chris - And yet, when we then, by 70,000 years ago or so, learn how to become much more adept at handling these environments, those other groups like the Neanderthals, like the Denisovans, who you're saying were there first, they no longer had that edge over us. So we could exit Africa and make it after that. And then we went everywhere. Andrea - Yeah, that's what we think. And probably we were so many that at that point, indeed, we did integrate some of the Neanderthals into us. There was a little bit of genetic material that comes from them. And so the Denisovans, but the wave at 50,000, just had a different demography. It was just a different number of people compared to what was there before.