These striking photographs tell a deadly story about climate change and dengue fever, generally the world’s fastest-spreading mosquito-borne disease.

Photographer ’s photo essay The Ascent of Temperatures explores how dengue has spread to Nepal’s Himalayan districts, including Chandannath, which, at 2438 metres above sea level, is one of the highest towns where Aedes aegypti and Aedes albopictus mosquitoes and their larvae have been discovered. Previously, these mosquitoes, which transmit dengue and other diseases, had been observed only at elevations of up to 2100 metres, according to the photographer.

Segalerba has been exploring “how traditional knowledge systems respond to external pressures”, and was investigating the spread of dengue into high-altitude areas in the Peruvian Andes when he learned of what was happening in Nepal. “It turned out to be the clearest setting for that question: a millennia-old medical tradition with its own framework for understanding illness, suddenly facing a disease it had never encountered before,” he says.

Recently, dengue has spread across most of Nepal, fuelled by climate change as well as increasing travel. According to , at least six people died of dengue in 2025 and around 9000 were infected, with the virus now having spread to 76 out of the country’s 77 districts.

Above, a female Aedes aegypti mosquito is shown in detail under a microscope. The Nepal 91ɫ��Ƭ Research Council (NHRC), working with the Institute of Tropical Medicine in Antwerp, Belgium, examines larvae and adult mosquitoes for changes in colour or shape that show they are becoming resistant to insecticides or adapting to different altitudes.

Below, Ishan Gautam, associate professor and chief of the Natural History Museum at Tribhuvan University in Kathmandu, shows Aedes larvae to students at Geetamata Secondary School, also in Kathmandu. The university organises awareness campaigns where local people are shown live Aedes mosquito larvae, and learn about their breeding habits and the importance of removing potential breeding sites like stagnant water.

In the image below, Amchi Khedup Loden Gurung packs traditional Sowa Rigpa (Tibetan) medicines in a clinic in Jomsom, northern Nepal.

Mosquito nets are being encouraged around Chandannath: below, local resident Devi Kannya Katayata breastfeeds her son Nehan Budha under a net at home.

In the image below, Sunita Baral, a PhD student at the NHRC, examines a mosquito inside a rearing cage. The council studies larvae and adult specimens from many habitats to discover more about the dengue-carrying mosquitoes circulating across Nepal.

Below, sheets are seen drying in the sun in the courtyard of Pokhara Hospital. Pokhara is the main gateway to the high-altitude region of Mustang, where Segalerba says dengue cases have recently been reported. Experts fear reported cases are a small fraction of the true infection level, he says, because around 90 per cent of infected people are asymptomatic, and many cases and deaths may go unreported.

We have read all sorts in the New Scientist Book Club, from Octavia E. Butler’s classic slice of dystopian fiction, Parable of the Sower, to space exploration in Adrian Tchaikovsky’s Alien Clay. Michel Nieva’s Dengue Boy (and this isn’t the article for you if you are yet to read it: spoilers ahead!) was something else entirely: a weird and technicolour vision of a dire future in a flooded world, where our perspective is that of a humanoid and homicidal mosquito.

There were parts of this novel that I loved, in particular Nieva’s wild inventiveness in dreaming up his future world. This is a place where the Antarctic ice thawed in 2197, and where rising sea levels mean that “Patagonia – a region once famous for its forests, lakes, and glaciers – was transformed into a disjointed trail of small, scorching-hot islands”.

Read an extract from Michel Nieva’s science fiction novel Dengue Boy

In this passage from Dengue Boy, the latest read for the New Scientist Book Club, we get an insight into life for Michel Nieva’s mosquito protagonist – and the drowned future world she inhabits

It is a place where, thanks to “the total deforestation of the Amazon and all the forests in China and Africa, hundreds of thousands of previously unrecorded viruses now appeared every year”. And where the endless and awful ingenuity of humanity mean people are now trading on the Financial Virus Index. Powered by quantum computers, this is “capable not only of determining with 99.99% efficacy which of these new viruses would unleash a new pandemic, but also of gathering shares in the companies likely to benefit from their effects and offering them up to the market in packages which sold like hotcakes”. Brilliant idea!

I also think Nieva’s writing (ably translated by Rahul Bery) occasionally leaps to elevated levels. At one point, our protagonist is early to school (because she can fly there, unlike her classmates snarled in traffic). She has to “wait there, completely still, for several minutes, hours even, not knowing what to do with her excessive corporality”. Excessive corporality! What a gloriously apt description for this miserable mosquito.

There is an unbearable poignance, which has stayed with me since finishing, in Nieva’s vision of a Great Iceberg Gallery, where the super-rich can go to see bits of ancient ice floes. “One could not walk through the Great Iceberg Gallery and not feel the sudden weight of the world in its infancy. A reliquary of true planetary jewels, its combined age was greater than that of all humanity.”

And I can only admire Nieva’s virtuosity in thinking himself into the mind of a murderous mosquito. I think he largely pulls this off, and I enjoyed how my sympathies half wanted to be with our “stubbornly homicidal” protagonist, and half were violently put off by her actions.

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Some of you also saw a lot of positives in the novel. “Once I worked out this is South American magical realism rather than science fiction, I’m enjoying it (big fan of Gabriel García Márquez, Italo Calvino and Umberto Eco). It’s a completely different genre,” wrote Emma Weisblatt on our Book Club , where all these comments are from. “It’s weird, surreal and allegorical and I think on those terms it works quite well.”

Michel Nieva on writing from a mosquito’s perspective for Dengue Boy

"What will happen in South America when the billionaires colonise space?" asks Michel Nieva, author of 'Dengue Boy' a nightmarish future tale where a humanoid mosquito seeks revenge in the ruins of an exploited Earth

For Terry James, the start of the book was difficult, as it requires a lot of suspension of disbelief to accept Nieva’s mosquito protagonist (and its implausible size) – and then you have to deal with the “rough language”. But Terry was glad he kept going. “The more I read, the more I enjoyed it. I found the literary technique of revealing the inner struggle of the poor alongside the absurd wealth, privilege, and opulent extravagance of the rich as extremely effective,” he wrote. “This book is creative.”

I think David Jones nailed it when he said it “wasn’t comfortable reading”, but he “actually quite enjoyed it”. “It’s a very dystopian satirical and quite gory view of the future. A day to read and a day to digest how I felt about it,” he wrote.

But – and perhaps this is because I’m not a connoisseur of steampunk, as the novel is described on its cover – I found much to dislike too. That “excessive corporality” I so enjoyed in the mosquito comes out in various scenes of violence and sexual depravity that I found difficult to read. I’m a Stephen King fan – I don’t mind a bit of horror and gore. But I didn’t really understand what the abundance of vulgarity brought to the story here, other than totally grossing me out. I hated the sheepies! Really hated them! (Some might say: that was the point, but for me it was a point I wasn’t keen to see made.)

And I found the parts of the novel when our mosquito was out on its bloody adventures far more compelling than the Borges-esque “computer game within a computer game” section that we got to later on. That was on the wrong side of surreal for me, or I just wasn’t getting it. Terry James also took issue with the “Mighty Anarch” component of the story and failed to grasp any meaning in it. “I call this kind of ideology pseudo-intellectual because it sounds very smart but is not meaningful in a holistic, integrated system,” he wrote.

Overall, for me, this wasn’t a book I’d return to, and I would say the majority of our members were also more negative than positive on this one. Judith Lazell found it “disappointing”. “Gratuitous sexual fantasy and undeveloped characters; violence explicit and revolting. Perhaps that was the point,” she wrote – although she did add that Nieva’s “description of the local environment [was] effective in evoking an awful place to live”.

For Eliza Rose and Andy Feest, it was their least favourite book club read so far. Like me, Eliza also wasn’t a fan of the body horror – but she liked the corrupt corporations part of the storyline. “I feel he did tell a story and I suppose ended it satisfactorily but I didn’t need all the gore,” she wrote.

Andy described the story as “plain weird”, and felt that while Nieva had come up with an interesting concept, he could have used a lot more backstory and detail. “The end was disappointing (not to say confusing too),” wrote Andy. “Overall, I was thankful that this was a shortish book as I am not sure I would have finished it if it were a larger novel (and I hate not finishing books I’ve started… and paid for).”

Perhaps Andy won’t have to pay for the next book we’ll be reading: Larry Niven’s , an old classic that many of you may have on your shelves. Come and tell us what you think of it on our , try out an extract here and get an insight into how Larry came up with the mechanics of his epic creation in this piece he’s written for us here.

The New Scientist Book Club has been reading Michel Nieva’s Dengue Boy, a tale of a demented future in which a humanoid mosquito, whose monstrous appearance repulses everyone, takes his revenge in the dying years of an exploited Earth. This week, our culture editor Alison Flood caught up with Nieva to delve into how he got into the mind of a mosquito, the importance of telling sci-fi stories from a South American perspective, and the inevitability of capitalism even at the end of the world.

Read more: New Scientist Book Club: Why I chose a mosquito as my hero

A deadly virus is killing blackbirds across the UK. Beyond the risk to the birds, its spread indicates that mosquito-borne viruses now pose a growing threat to humans and animals in the country, in part as a result of climate change.

The virus in question, Usutu, originated in South Africa in 1959 but is now widespread in Europe. It causes deadly disease in certain bird species, particularly blackbirds, and was first detected in the UK in 2020. In some parts of the country, most notably London, blackbird populations have dropped by more than 40 per cent since 2018. “We first noticed the decline at the same time as Usutu popped up,” says at the British Trust for Ornithology.��

Although devastating for bird life, Usutu poses a low risk to humans and mammals. Infections in people are rare and generally only cause a mild fever, but the arrival of the virus in the UK marked the first time a mosquito-borne viral zoonosis – a disease that can be transmitted from an animal to a human – had emerged in animal hosts in the country. Virus experts are keeping a close watch on how far and fast the disease is spreading because it could be a template for the future spread of other mosquito-borne diseases. ��

For example, the West Nile virus spreads in the same way as Usutu and requires the same environmental conditions. “The same mosquitoes that can transmit Usutu typically can transmit West Nile, and the same birds which act as hosts [for Usutu] can also act as hosts of West Nile,” says at the UK’s Animal and Plant 91ɫ��Ƭ Agency (APHA).��

Humans can also be infected by West Nile virus from a mosquito bite, but its symptoms can be more severe than those of Usutu. Around 20 per cent of those infected will experience symptoms, which include fever, headache, body aches, vomiting and diarrhoea. In rare cases, the virus can cause serious inflammation of the brain and spinal cord, which can be fatal. There is no known human vaccine.

Climate change has helped accelerate the spread of West Nile virus through northern and eastern Europe, , as the virus thrives in warm summer temperatures. In the Netherlands, Usutu was first detected in 2016 and West Nile virus followed in 2020.��UK officials fear a similar pattern will play out in their country, with ��that the climate there is becoming increasingly hospitable to mosquito-borne viruses. “The idea is that, if we have Usutu here, West Nile is probably going to come at some point and is likely to persist, given the right conditions,” says Folly.

In response to the threat, APHA launched a project in 2023 to track the emergence and transmission pathways of Usutu and other mosquito-borne viruses in wild birds. This virus-tracing infrastructure will be vital if the country is to respond quickly to West Nile’s arrival, says Folly. “Our real goal, or drive from a governmental point of view, is to be able to detect these [new viruses] circulating in animal populations before we get transmission to humans.”

at Erasmus University Medical Center in Rotterdam has been studying the emergence of Usutu and West Nile virus in the Netherlands. Although West Nile hasn’t been detected since 2022, she believes the virus is circulating at a low level, kept in check currently by the country’s relatively cool climate. “I believe it is present, but it needs the right circumstances to flare up,” she says. A UK detection of West Nile is now all but inevitable, says Sikkema, but she believes similar climatic factors could prevent the virus spreading too widely for now.

But rising summer temperatures, including the – which the UK’s Met Office weather agency defines as when minimum temperatures fail to fall below 20°C – could change the picture in the UK, the Netherlands and other northern European nations in coming years, warns Sikkema. “Mosquito-borne disease is not [just] on your Spanish holiday or when you go to the South Americas,” says Folly.

As well as the potential risk of West Nile virus to people, Folly says we shouldn’t forget what Usutu is doing to the UK’s blackbirds: “If 40 per cent of humans dropped dead in Greater London, you’d know about it quite quickly.”

The idea that the hero of would be a mosquito emerged in 2020, during the peak of the covid-19 pandemic, when a dengue outbreak exploded in my hometown, Buenos Aires. Dengue fever spreads through the Aedes aegypti mosquito. This insect thrives in tropical and subtropical climates and is common in many warm and humid regions of northern Argentina.

However, in recent decades, due to global warming, it has spread to regions where the climate has traditionally been cold or temperate, such as Buenos Aires and even Patagonia. It so happened that one of my best friends became infected with dengue in 2020, but since all the media attention was focused on covid-19, public hospitals in the city had restricted tests and there was no way to get a proper diagnosis or treatment. Furthermore, there were no effective vaccines or medications for dengue at the time.

During this precarious time for my friend and for the people with dengue in Argentina, the US company Moderna announced its vaccine against covid-19, just a few days after the genetic sequence of SARS-Cov-2 was published. This made me think about the terrible corporate bias in scientific research, as mosquito-borne diseases (dengue, zika, chikungunya, yellow fever, among others) have been killing hundreds of thousands of people for centuries. The mosquito, in fact, is considered the deadliest animal to humans, and according to historian , it has killed more humans than anything else in history.

However, because these diseases affect people in lower-income countries, there was never adequate investment in vaccines or treatments. Meanwhile, biotechnology companies only needed months to develop, patent and sell products tackling covid-19, which ensured them substantial monetary profit.

So, the idea came to me to tell the story of a Global South pandemic, through the lens of the mosquito itself.

Partly inspired by artists I admire (Franz Kafka, David Cronenberg, Hideshi Hino) and leaning a little ironically into the most commercially popular genre in Latin America, autofiction, I became convinced that my story’s imaginary subtitle should be “the autofiction of a mosquito”. At the same time, one of the themes in my writing is the non-human, and I was interested in the challenge of making an insect the protagonist of a novel (a genre historically designed to narrate human times, psychologies and stories). How to mimic and achieve empathy with a creature so alien to the human experience as an insect, particularly one as annoying as the mosquito?

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I had to become a mosquito, adopt its perspective. I appropriated the famous Flaubertian motto “Madame Bovary, c’est moi” and turned it into my own: le moustique, c’est moi.

Ursula K. Le Guin once said the , allowing the migration of ideas from fiction to other scientific and technical discourses. In this way, the genre becomes a mutant transition (as Dengue Boy is) between literature and non-literary knowledge.

I have always greatly appreciated this idea, because nothing pleases me more in my task as a writer than researching topics I would never have even noticed before.

For this book, I consulted dozens of papers and manuals on entomology and I became a “mosquitologist” overnight. It was crucial to know the details of the mosquito’s anatomy in order to describe it and understand how its body works and feels. Thus, although the protagonist is inspired by my friend, who is a man, I discovered that the mosquitoes that transmit disease are female, which forced me to transform my plot on the spot.

The female perspective also led me to investigate how a non-mammalian, oviparous animal engages in maternal care – if it does at all – and I became captivated by ovology and the representation of eggs. The eggs designed by H.R. Giger for the movie Alien, those drawn and classified by naturalist Ernst Haeckel in his illustrated treatises, and Georges Bataille’s Story of the Eye also fuelled this ovophilic obsession.

In this novel, I tried to tell a story about climate change from a perspective that recovered more-than-human lives, and I hope the reader empathises with my hero – just as I also became a mosquito while conceiving and imagining it.

by Michel Nieva, translated from Spanish by Rahul Bery and published by Serpent’s Tail, is the latest pick for the New Scientist Book Club. Sign up and read along with us here