When he bought the pretty little striped field mouse on the internet for $8 to give to his daughter for her sixth birthday, the businessman from São Paulo was told it was free of infection and had been bred by a registered dealer. In fact, it had been sourced from the vast sugar cane fields planted in Brazil to grow biofuels to reduce the use of fossil fuels – and which were swarming with rodents after yet another heatwave.
It nipped his daughter on the finger, but no one thought much of it – and six days later, he left on a trip to Europe. By the time he reached Amsterdam, she had started suffering fevers, muscle aches and breathing problems and had been rushed to hospital, and he too felt unwell. It was the start of one of the worst pandemics in human history, killing more people than Covid-19, Sars or the 1918 flu pandemic put together.
In one week 300 people had been infected, a month later 300,000 people around the world were gasping for breath. After 8 months, possibly 20 million people had died and 1 billion people were infected. It was Covid on steroids. Whereas Covid killed 1% of people infected, this novel hantavirus mutated as fast as the Omicron variant and killed one in three people it infected. It was Disease X, the name adopted in 2018 by World Health Organization disease experts to an as yet unknown, hyper-virulent disease for which no drug or vaccine was available, but which could kill hundreds of millions of people.
That much is fiction. Disease X is hypothetical. But the consensus is that something like it is coming. It may not be a hantavirus. It could well be a flu, a coronavirus like Covid-19, or a returning, souped-up ancient killer like typhoid, tuberculosis or plague. It may spill over to humans through a hamster, a bat, a chicken, or a tick. It could come out of a fur farm in Norway or a pig farm in Mexico. It could incubate in a disturbed forest, a US weapons lab or a farmers’ market in the UK. It may not arrive for many decades but with climate change, new global ecological conditions, hyper-mobility and ever denser human and animal populations, another great pandemic is inevitable.
Pandemics kill far more people and cost economies more than war, but no government or global body at present plans to address the underlying cause of Covid-19 or the question of why outbreaks of major new infectious diseases like HIV/Aids, Ebola, Marburg, avian flu, Sars, Middle East respiratory syndrome (Mers), mpox and Nipah have all emerged in the past 50 years. The priority of government and industry is to find better ways to treat symptoms with better vaccines and technology, rather than address the causes of disease.
But we are not helpless. We know enough to strongly expect the next great pandemic will be “zoonotic” (or linked to animals), be ecologically driven and connected to the way humanity manipulates, changes and degrades the global environment. Intensive deforestation, the draining of wetland, climate change, the degradation of soil, the collapse of biodiversity, and the growth of vast, impoverished cities have together helped create the perfect conditions for new viruses to evolve faster, emerge more easily and cross from one species to another.
Covid has taught us that we cannot stop the evolution of microbes or escape from them. There are at least six things we can do, however, to not only reduce the risk of pandemics emerging but also reduce their severity.
Rethink human relationships with animals. Animals have played a major part in nearly every major disease outbreak since 1970. In that short time, about 500 new zoonotic, or animal-born diseases have emerged, including Mers, avian influenza, Ebola, Marburg, Lassa, Nipah, Zika, Covid-19 and HIV/Aids. Humans have never been closer to the pathogens of other species.
Reform farming. We have never farmed so many animals so intensively: over 70 billion of them a year are slaughtered for meat. Global food production now relies on vast flocks and herds of genetically identical poultry, cattle and pigs being reared in high-intensity, overcrowded, confined, entirely unnatural conditions. The growing danger is that industrial farms are becoming disease factories, incubating and enhancing pathogens like flu, and enabling hyper-virulent pathogens to spread within flocks or cross to humans.
Restore ecosystems. The past 30 years have seen an astonishingly fast transformation of the world’s forests, wetlands and soils to provide food; the greatest mining and extraction of fossil fuels for energy, power and minerals in human history; and the biggest increase ever known in trade and human travel. Logging, urbanisation and human population growth have all fragmented ecosystems and helped create the condition for diseases to emerge and spread. We must minimise the disturbance of nature and reduce the interactions between ourselves and the pathogens of other species.
Control greenhouse emissions. Global heating increases the threat of diseases emerging – and changes where and when they emerge and spread. When temperatures rise, rains are heavier or droughts and heatwaves last longer, then the conditions for life change – and the insects, bats, ticks and other wildlife that mostly carry pathogens or diseases like malaria, Rift Valley fever, cholera and dengue are likely to geographically spread. The changing climate is already driving wildlife into new areas, destroying habitat and forcing it to survive in new ecological conditions in which previously isolated species may mix and exchange pathogens. Unless climate heating is brought under control, not only will humanity suffer, but there are likely to be many new diseases emerging, and in unexpected places.
Control lab experiments. There is no consensus on the origin of Covid-19, but the risk of a pandemic starting in a laboratory is real, and grows every year. Medical and military research uses the world’s most dangerous bacteria, viruses and pathogens and is now conducted in thousands of state, corporate and academic laboratories around the world. New ways to find vaccines and control dangerous pathogens are now a multibillion-dollar global industry. The risk of future pandemics originating from controversial “gain-of-function” research that aims to increase a pathogen’s virulence for possible military or medical use is high.
Improve disease surveillance. Infectious diseases will continue to break out, mutate and haunt us. But who they affect and where they strike now depends on us. Strong public health systems, especially in the world’s great urban centres, are best placed to monitor new disease outbreaks, to identify what strains may be spreading and to test and stop them in their tracks. But that requires commitments by all countries to invest heavily in eradicating global poverty. This may be the global north’s best insurance policy against future pandemics.
Eliminating the risk of infectious disease is as impossible now as it was 20 years ago, but if we only try to treat the symptoms of disease with vaccines and technology, we are in danger of not preventing them occurring in the first place. The only way to ensure good long-term human and planetary health is to minimise the disturbance of nature – and avoid interactions between ourselves and the pathogens of other species.
John Vidal is the Guardian’s former environment editor and author of Fevered Planet: How Diseases Emerge When We Harm Nature (Bloomsbury, £20). To support The Guardian and Observer, order your copy at guardianbookshop.com. Delivery charges may apply.