Why scientists fear climate change could help Covid to thrive
To date, more than 778 million cases across 240 countries have been reported by the World Health Organisation, with new variants continuing to emerge.
While globalisation and international transport are well-known drivers of the rapid spread of the virus, emerging research suggests climate change can influence Covid-19 transmission, mutation, and human susceptibility to infection.
Researchers believe that increased exposure to animals, that can carry viruses and transmit them to humans, may lead to a rise in cases.
'As we disturb natural ecosystems and bring wildlife, especially bats in the case of Covid, into closer contact with other animals and people, the risk of diseases jumping between species increases,' Dr Efstathios Giotis, Infectious Disease Research Fellow at Imperial College London, told The Independent.
'In fact, there is growing evidence that SARS-CoV-2 may have first jumped from bats to an intermediate animal, such as raccoon dogs, before eventually infecting humans.'
After initial debate, there is now broad scientific consensus that bats were the so-called reservoir, where Covid pathogens existed and multiplied.
Changing weather patterns and ecosystems have increased human contact with wildlife and created conditions conducive to viral survival.
Extreme weather events further exacerbate exposure, susceptibility, and strain emergency responses.
As noted by experts in The Lancet Planetary Health, the emergence of Covid-19 coincided with one of the hottest years on record, marked by notable climatic extremes.
Record-breaking heat, rising sea levels, melting ice, and extreme weather reinforced evidence that the Earth is undergoing dangerous change for key climate indicators, according to the latest State of the Global Climate report.
Last year was the first in which the average global temperature exceeded 1.5 °C above pre-industrial levels, with extreme weather events leading to the highest number of new displacements since 2008, the report said.
Transmission
Covid-19 is transmitted through tiny airborne droplets when an infected person breathes, speaks, sneezes or coughs.
Rising temperatures and relative humidity help infectious particles survive longer and remain suspended in the air, influencing transmission, scientists explained in a paper published in Frontiers in Medicine.
Increased rainfall, flooding, and climate-driven displacement forces people into close contact, boosting infection chances and contributing to higher prevalence in areas with high population density. Displacement also makes hygiene practices harder to maintain, the UNHCR emphasised.
More widely, deforestation increases the risk of transmission for zoonotic diseases, passed from animal to human, and potentially new coronaviruses.
'The big issue of novel zoonotic disease is how we have eroded ecosystems and their natural regulation of disease transmission,' Dr Mark Everard, Ecosystem Services Professor at the University of the West of England told The Independent.
Habitat loss and expanding roads into less degraded areas reduce the buffer natural habitats create from humans, Dr Everard explained.
Mutation
As habitat and buffer loss increases the chance of coronavirus jumping or 'spilling' from animals to humans, it increases the likelihood of mutations occurring.
'Climate doesn't directly change how fast pathogens mutate, but it can create more chances for mutations to happen,' Dr Efstathios Giotis told The Independent.
'For example, when climate events occur such as unusually warm temperatures or habitat changes (such as a bushfire), they can push animals into closer contact with other species or humans.
'In this way viruses like influenza or coronaviruses have more opportunities to jump or spillover between species.
'Each spillover event increases the chances for new mutations to develop.'
Susceptibility
Climate factors can also make people more susceptible to Covid-19.
Dust from desertification damages the respiratory tract, giving the virus deeper access and increasing disease severity, research in Frontiers in Medicine explained.
In the case of wildfires, tiny particulate matter, known as PM2.5, in smoke irritate and inflame the lungs, increasing the risk of infection. Measuring just 2.5 micrometers in diameter, PM2.5 enters the blood stream and lodges deep in organs.
This risk increases for children, with small lungs, or people with pre-existing organ conditions, research in the The Lancet Planetary explained.
'Organisms stressed by heat, water, etc. have lower resistance to infections,' added Dr Everard, referring to plants, animals or humans who either carry infections or are infected.
Emergency responses
Climate hazards can interfere in the delivery of public services and staff mobilisation, research in The Lancet added.
For example, power disruptions can affect health facilities and wildfires divert emergency staff attention.
Contract tracing also becomes harder as, for example, people move and intermingle in response to flooding.
While research into the links between climate and Covid-19 is still ongoing and some studies are inconclusive, the experts warned: 'Multiple risks can all affect health systems, leading to negative outcomes for people and locations with low capacities to respond to Covid-19.'
Hashtags
Try Our AI Features
Explore what Daily8 AI can do for you:
Comments
No comments yet...
Related Articles
The Independent
4 hours ago
- The Independent
Why scientists fear climate change could help Covid to thrive
From Indigenous communities in the Amazon to the frozen continent of Antarctica, the Covid-19 virus has spread at an unprecedented pace to some of the world's most remote areas after it was first reported in Wuhan in December 2019. To date, more than 778 million cases across 240 countries have been reported by the World Health Organisation, with new variants continuing to emerge. While globalisation and international transport are well-known drivers of the rapid spread of the virus, emerging research suggests climate change can influence Covid-19 transmission, mutation, and human susceptibility to infection. Researchers believe that increased exposure to animals, that can carry viruses and transmit them to humans, may lead to a rise in cases. 'As we disturb natural ecosystems and bring wildlife, especially bats in the case of Covid, into closer contact with other animals and people, the risk of diseases jumping between species increases,' Dr Efstathios Giotis, Infectious Disease Research Fellow at Imperial College London, told The Independent. 'In fact, there is growing evidence that SARS-CoV-2 may have first jumped from bats to an intermediate animal, such as raccoon dogs, before eventually infecting humans.' After initial debate, there is now broad scientific consensus that bats were the so-called reservoir, where Covid pathogens existed and multiplied. Changing weather patterns and ecosystems have increased human contact with wildlife and created conditions conducive to viral survival. Extreme weather events further exacerbate exposure, susceptibility, and strain emergency responses. As noted by experts in The Lancet Planetary Health, the emergence of Covid-19 coincided with one of the hottest years on record, marked by notable climatic extremes. Record-breaking heat, rising sea levels, melting ice, and extreme weather reinforced evidence that the Earth is undergoing dangerous change for key climate indicators, according to the latest State of the Global Climate report. Last year was the first in which the average global temperature exceeded 1.5 °C above pre-industrial levels, with extreme weather events leading to the highest number of new displacements since 2008, the report said. Transmission Covid-19 is transmitted through tiny airborne droplets when an infected person breathes, speaks, sneezes or coughs. Rising temperatures and relative humidity help infectious particles survive longer and remain suspended in the air, influencing transmission, scientists explained in a paper published in Frontiers in Medicine. Increased rainfall, flooding, and climate-driven displacement forces people into close contact, boosting infection chances and contributing to higher prevalence in areas with high population density. Displacement also makes hygiene practices harder to maintain, the UNHCR emphasised. More widely, deforestation increases the risk of transmission for zoonotic diseases, passed from animal to human, and potentially new coronaviruses. 'The big issue of novel zoonotic disease is how we have eroded ecosystems and their natural regulation of disease transmission,' Dr Mark Everard, Ecosystem Services Professor at the University of the West of England told The Independent. Habitat loss and expanding roads into less degraded areas reduce the buffer natural habitats create from humans, Dr Everard explained. Mutation As habitat and buffer loss increases the chance of coronavirus jumping or 'spilling' from animals to humans, it increases the likelihood of mutations occurring. 'Climate doesn't directly change how fast pathogens mutate, but it can create more chances for mutations to happen,' Dr Efstathios Giotis told The Independent. 'For example, when climate events occur such as unusually warm temperatures or habitat changes (such as a bushfire), they can push animals into closer contact with other species or humans. 'In this way viruses like influenza or coronaviruses have more opportunities to jump or spillover between species. 'Each spillover event increases the chances for new mutations to develop.' Susceptibility Climate factors can also make people more susceptible to Covid-19. Dust from desertification damages the respiratory tract, giving the virus deeper access and increasing disease severity, research in Frontiers in Medicine explained. In the case of wildfires, tiny particulate matter, known as PM2.5, in smoke irritate and inflame the lungs, increasing the risk of infection. Measuring just 2.5 micrometers in diameter, PM2.5 enters the blood stream and lodges deep in organs. This risk increases for children, with small lungs, or people with pre-existing organ conditions, research in the The Lancet Planetary explained. 'Organisms stressed by heat, water, etc. have lower resistance to infections,' added Dr Everard, referring to plants, animals or humans who either carry infections or are infected. Emergency responses Climate hazards can interfere in the delivery of public services and staff mobilisation, research in The Lancet added. For example, power disruptions can affect health facilities and wildfires divert emergency staff attention. Contract tracing also becomes harder as, for example, people move and intermingle in response to flooding. While research into the links between climate and Covid-19 is still ongoing and some studies are inconclusive, the experts warned: 'Multiple risks can all affect health systems, leading to negative outcomes for people and locations with low capacities to respond to Covid-19.'
The Guardian
9 hours ago
- The Guardian
‘A disaster for all of us': US scientists describe impact of Trump cuts
'Our ability to respond to climate change, the biggest existential threat facing humanity, is totally adrift,' said Sally Johnson, an Earth scientist who has spent the past two decades helping collect, store and distribute data at Nasa (National Aeronautics and Space Administration) and Noaa (National Oceanic and Atmospheric Administration). Donald Trump's assault on science – but particularly climate science – has led to unprecedented funding cuts and staff layoffs across federally funded agencies and programs, threatening to derail research tackling the most pressing issues facing Americans and humanity more broadly. A generation of scientific talent is also on the brink of being lost, with unprecedented political interference at what were previously evidence-driven agencies jeopardizing the future of US industries and economic growth. Johnson was among scores of scientists conducting vital research across a range of fields from infectious diseases, robotics, education, computer science and the climate crisis, who responded to a Guardian online callout to share their experiences about the impact of the Trump administration's cuts to science funding. Many said they had already had funding slashed or programs terminated, while others fear that cuts are inevitable and are beginning to search for alternative work – either overseas or outside science. So far, the cuts have led to a 60% reduction in Johnson's team, and fear is mounting over the future of 30 years of climate data and expertise as communities across the country are battered by increasingly destructive extreme weather events. 'We won't be able to afford to continue providing the free and quality tools and services to make our data stores searchable, viewable, usable, and accessible. We might not even be able to afford to keep all the data … this will mean worse forecasts and less effective search and rescue responses leading to unnecessary and avoidable loss of life,' said Johnson (not her real name). Trump's One Big Beautiful Bill Act (Obbba) calls for a 56% cut to the current $9bn National Science Foundation (NSF) budget, as well as a 73% reduction in staff and fellowships – with graduate students among the hardest hit. The NSF is the premier federal investor in basic science and engineering, and more than 1,650 grants have also been terminated, according to Grant Watch, a non-profit tracking federally funded research grants under the Trump administration. At the behest of Trump, the hardest hit are studies aimed at addressing the unequal impact of the climate crisis and other environmental hazards, as well as any projects perceived to have a connection to diversity, equity or inclusion (DEI). An anthropologist who researches the impact of floods and cyclones on public health and food supplies in Madagascar, which is among the most vulnerable nations in the world to the climate crisis but contributed virtually nothing to the catastrophe, is leaving Johns Hopkins for Oxford University after funding for the remainder of her fellowship was threatened. 'I am devastated to leave family, friends and the grad students I am mentoring in the US, but this seemed like the only way to continue work I've been pursuing for 10+ years. I am working on improving climate mitigation and adaptation in an African country. After Trump was elected, the writing was on the wall. There is no way I can write grant applications that will be acceptable to this government.' A veteran infectious diseases researcher at Ohio State University was forced to abandon a clinical trial for a new medication to treat hypoxemic respiratory failure in Covid patients after the National Institute of Health (NIH) terminated funding midway through the study. The decision will save $500,000, but $1.5m had already been spent on the trial which researchers hoped would lead to new treatment options for the million or so people hospitalized with respiratory failure each year as a result of flu, Covid and other infections. The trial would have to be repeated from the start, in order to seek approval from the FDA. 'This is a disaster for all of us. We're all depressed and living on a knife-edge, because we know we could lose the rest of our grants any day. These people really hate us yet all we've done is work hard to make people's health better. A flu pandemic is coming for us, what's happening in cattle is truly scary and all we have is oxygen and hope for people,' said the Ohio scientist. Between 90 and 95% of their lab work is funded through the NIH. So far, more than 3,500 grants have been terminated or frozen by the NIH. Trump's budget proposes slashing NIH funding by more than 40%. The majority of scientists who got in touch described feeling anxious and despondent – about their own work if the cuts continue, but also about what seems an inevitable loss of talent and knowledge which could upend the US position as a global leader in scientific endeavors and ricochet for years to come. The brain drain is real. The Australian Academy of Science is leading the country's efforts to proactively recruit top US-based scientists, creating a new global talent program that includes research funding, access to Australian research infrastructure, fast-track visas and a relocation package. At least 75 scientists applied in the first three months of the program, the AAS told the Guardian. The Trump administration has accused universities, without evidence, of promoting leftwing radical thinking and research, but federal funds train scientists who go on to work for the oil and gas, mining, chemical, big tech and other industries. Several respondents said the private sector was also starting to feel the knock-on effect of Trump's cuts and tariffs. Wessel van den Bergh, a materials scientist with a PhD, was working on battery storage technology for a Chinese-owned renewable energy company in Massachusetts. He was laid off in early June amid Trump's tariff chaos and attacks on science and renewables, and is struggling to find work. 'When I started my PhD program, America was at the leading edge of batteries/energy storage but this is no longer true due to tariffs, funding cuts, and aggression towards green alternatives. Rather, the US has ceded its hard-earned expertise to other countries such as Korea, Japan and China,' Van den Bergh said. Trump supports the expansion of fossil fuels and has received millions of dollars in campaign donations from the oil, gas and coal industry, while his budget legislation terminated incentives for solar and wind energy. 'It's crushing, I don't see a clear path ahead any more. I no longer feel this country values science. It's genuinely heartbreaking to build your vocation to something that could genuinely benefit the world for it to be quashed for imagined political victories … especially at a time where these kinds of technologies are the only way out of the climate crisis,' said Van den Bergh. Separately, the Nuclear Physics Laboratory (NPL) at the University of Illinois got in touch after the Guardian's recent investigation into the chaos at the NSF. For almost 100 years the NPL has been at the forefront of cutting-edge science in drug discovery, cancer treatments, PET scans and other medical diagnoses, and semiconductor testing, with researchers playing a key role in world-renowned institutions like Cern and Los Alamos. It's a major hub for nurturing and training future talent, and at least 50 students have graduated with PhDs in the past 20 years. It was here that Rosalind Yalow got her PhD in nuclear physics in 1945, and then went on to invent radioimmunoassay – a technique to detect minute amounts of hormones, viruses and drugs in the blood which revolutionized medical testing for conditions such as diabetes. Yalow was awarded the Nobel prize in 1977, only the second woman to win it. The lab was recently informed that the NSF will reduce funding that supports graduates students from $15m for four years to $1m for one year. 'Our group in nuclear physics at Illinois actually predates the founding of the NSF in 1950, and we have a long history of both producing scientists and accelerator technologies that have had an impact on huge numbers of people,' said Anne M Sickles, professor of nuclear physics. 'If you cut the funding to the people who are doing the work right now, you don't know what they would have innovated in 10 years or 15 years or 32 years like Rosalind Yalow. We don't know what we're losing.' The NFS declined to comment, while the office of management and budget and NIH did not respond.
Telegraph
14 hours ago
- Telegraph
The bizarre trees that ‘milk' clouds and start lightning storms
Thanks to Harriet Rix and her sublime book, The Genius of Trees, I have seen and relished the world the day before the Chicxulub asteroid hit. I have smelled its perfumes, and squelched through its hot boggy litters, and dodged its foot-long dragonflies. And I have seen the day after, too, 'when all was darkness and confusion, mushrooms and rot'. Rix's book explains how over millennia, trees have shaped the earth and been shaped by it. (They allowed for the existence of those monster dragonflies by saturating the atmosphere with oxygen, for starters.) Trees thrived before Chicxulub, Rix tells us, but afterwards, their 'green shade became a grey gloom' as a dust cloud blotted out the sun for two years. The Amazon became a death zone. Gymnosperms – meaning pines and monkey puzzles – were utterly outmanoeuvred by flowers, which could survive by bouncing light about themselves between water droplets. (Through Rix's luminous descriptions, I pictured this as a microscopic pinball game played with light, where the winner inherits the Earth.) Her book is a dazzling series of lectures which explore how trees shape water, soil, fire, air, fungi, animals and people. Like an early Robert MacFaralane narrator, Rix refuses to put herself much in the picture, but through the scenes we glimpse an Indiana Jones figure who is both an eminent, travelling scientist and a born writer. She describes the 'stately galliards' of coniferous trees taking over after the asteroid's destruction. To Rix, they arrive in 'a mass tango, angular and fluid'. On the Canary island of La Gomera, we encounter trees that not only make clouds, but farm and milk them, seeding the air with compounds which cause water molecules to cluster around them, 'until like a small planet, it falls as rain'. She also travels to the environs of Quetta to look at the Ziarat junipers, guarded by Balochi rangers in one of the world's deadliest zones of human conflict. Here, wild ephedra is easily and popularly synthesised into methamphetamine (do you prefer your Taliban on opium or speed?) Rix is completing a spreadsheet on juniper carbon capture when she's reassured that she won't be kidnapped, as long as she visits their food market twice. And by the time we have watched the beautiful Zelkova abelicea on Crete turn red when the first frosts fall, and have paddled up the Curicuriari, an Amazon river, to meet a rare duraka tree, it becomes clear that Rix's world is astounding. There are some mountains in deep, rural China where 18 species of tree are currently in a pitched brawl, using poison, shade, theft, disease, fire, misdirection, brute force and lighting on each other. This is normal tree behaviour, and it's a salutary experience, having been near woods most days of my life, to realise that I had little idea what I have been looking at. In their battles, trees lace the air with flammable gases, strew kindling, douse everything in the pyromaniac's molecule, oxygen, and gather clouds to encourage lightning strikes, which they have put up conductors to catch. Then, whoosh: their competition is vaporised, their insect pests barbecued, their fungi put in their place, their seed children pre-fertilised (lovely ash) and suddenly, there's a lot more sunlight to eat. When you see Greek islands scorched, know there is a pine or eucalyptus somewhere rubbing its roots together. Trees can change 'their entire habit of growing in one or two generations'. We know when the land-bridge between Britain and Ireland went (the sunken kingdom of Cantre'r Gwaelod under Cardigan bay) because lime trees, spreading slower than pioneer species, did not make it out of Wales. The climate in Ireland tipped from Arctic to temperate in just 10 years. The book is often alarming but Rix is also funny. Oak die-back happens, in Rix's eyes, when the trees' 'farthest fungi' have 'lost their love of adventure, their passion for the quest'. You feel delightedly child-like, and not just while being shown how a member of the avocado family seeds a cloud with a hexagonal ring of carbon. The mysteries stalking science and Rix's pages are telling. We still do not know how trees' roots appear to be able to 'hear' or sense water. It might be vibration. What's the real evolutionary relationship between the Joshua Tree of the Mojave Desert, the giant sloth with the mushroom-alcohol body odour, and the sloth's on-board moth? Only time, and Harriet Rix, can tell. Non-fiction rarely sees a debut like The Genius of Trees. It is a true masterpiece.
