The coronavirus pandemic has highlighted humanity's growing vulnerability to emerging infectious diseases and underscored the need to reduce our collective exposure to these pathogens. Not surprisingly, then, the past year has seen a torrent of reports on pandemic preparedness, including one I co-authored for the Council on Foreign Relations. Most of these focus on controlling outbreaks after they start, rather than averting them in the first place. Moving from reaction to prevention requires identifying and mitigating the main drivers of new infectious diseases. These drivers are almost entirely anthropogenic and are the same forces responsible for precipitous declines in global biodiversity. The path to global health security, in other words, begins with protecting nature.

We have entered a new era of infectious disease. In the past several decades, more than 400 new pathogens have emerged in humans. About 75 percent of these are zoonoses, or diseases that originated in wild animals before jumping to people, often through an intermediate host. SARS-CoV-2, the virus that causes COVID-19 and which originated in bats, is only the latest example, following on the heels of HIV/AIDS, Ebola, SARS, Nipah, West Nile, Zika, MERS, H5N1, H1N1 and many others. Economists estimate the average annual global cost of emerging zoonotic disease at more than $1 trillion, with periodic severe pandemics like COVID-19—for which projections of lost economic growth through 2025 go as high as $28 trillion—capable of inflicting much more damage.

It is tempting to treat pandemics as acts of God, but they are human-made, a function of our unsustainable exploitation of nature, which exposes us to new pathogens, and of our transportation networks, which help these new pathogens spread around the world. Three of the most important factors behind the rise in zoonoses are: changing land-use patterns, as human populations encroach upon, disturb, fragment and degrade habitats and come into closer contact with once-isolated species; relentless expansion and intensification of agriculture and animal husbandry, as biodiverse ecosystems give way to artificial monocultures and domesticated species become reservoirs for circulating zoonoses; and the burgeoning global wildlife trade, both legal and illegal, which affords viruses multiple opportunities to jump from exotic species to humans.

Given these linkages, pandemic prevention efforts must be grounded in a "One Health" approach that recognizes the intimate interconnections among human, animal and environmental health. Four priorities for multilateral cooperation stand out.

The first should be to create a high-level international panel on pandemic prevention, analogous to the Intergovernmental Panel on Climate Change, as proposed by the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services, or IPBES. Such a panel would help break down existing barriers among multilateral institutions as well as national agencies currently devoted to human, animal and environmental health. It would ideally serve as a repository of authoritative, policy-relevant scientific knowledge on emerging zoonotic risks and hot spots; lay the foundations for a global monitoring and surveillance network; and help build global consensus behind a "One Health" strategy based on concrete goals and targets, supported by national commitments akin to those made under the Paris climate agreement. It would also help consolidate nascent cooperation among diverse international agencies and frameworks, including the World Health Organization, the Global Health Security Agenda, the World Organization for Animal Health, the Food and Agriculture Organization, the United Nations Environment Program and the secretariats of the Convention on Biological Diversity and the Convention on International Trade in Endangered Species, or CITES.

The second global objective should be to arrest land degradation and agricultural expansion. This October, parties to the Convention on Biological Diversity, or CBD, will meet in Kunming, China, to endorse a new strategic framework for global conservation. A centerpiece of that agreement will be a commitment to permanently protect 30 percent of the Earth's land and water by 2030, known as the 30x30 initiative. The need is urgent. Humans have already transformed more than 70 percent of the planet's ice-free land surface, primarily for agriculture and ranching, as well as for mining and human settlements.

Beyond endangering the survival of wild species and ecosystems, the despoilation of nature threatens global health security. In addition to endorsing 30x30, parties to the CBD should incorporate health risk assessments into their national biodiversity action plans, including their designation of protected areas, as well as into their overall development strategies and land-use decisions. Governments should consider not only the damage that continual agricultural expansion and intensification does to their stock of natural capital assets and the ecosystem services that these provide, but also the health risks and costs these trends may impose on their populations. The quest for food security cannot come at the expense of health security.

Third, national governments and international organizations must reduce the pandemic risks of the global wildlife trade. The threat to human health posed by the wild animal trade is well-established, having contributed to the SARS pandemic and possibly to COVID-19. The scope of this global market is vast. The legal wildlife trade has ballooned fivefold since 2005 and twentyfold since the 1980s. One in four vertebrate species is now bought and sold across borders. The illegal wildlife trade, although smaller, generates an estimated $7 billion to $25 billion per year.

Curbing the threat of zoonoses will require closing legal loopholes in legal wildlife trade as well as cracking down on illicit trafficking. As a start, parties to CITES should amend that treaty, tightening international regulations on trade in high-risk endangered species, so that legal imports and exports do not endanger either human or animal health. In parallel, national governments should empower the World Organization on Animal Health and CITES to create a global surveillance and monitoring network capable of inspecting shipments and testing for high-risk pathogens in all species traded across borders. Simultaneously, parties to the U.N. Convention Against Transnational Organized Crime should negotiate a fourth protocol to the convention that criminalizes illicit trafficking in wild species and commits the parties to cooperate in curtailing such trade, including by adopting and enforcing domestic laws and stringent customs controls.

Finally, the world needs a better empirical understanding of the linkages between biodiversity and pandemics. The IPBES estimates that wild birds and mammals are host to some 1.7 million viruses, perhaps half of which may be capable of infecting humans and fewer than 0.1 percent of which have been identified. Improving the state of knowledge about global microbial diversity, including the prevalence and spillover risk of pathogens, is critical to identifying, mapping and monitoring potential hot spots for emerging infectious diseases and assessing zoonotic vulnerabilities created by environmental degradation, agricultural expansion and wildlife trade.

IPBES calculates that the global investment required to prevent pandemics by curtailing the wildlife trade, adapting land-use patterns and increasing "One Health" monitoring and surveillance capabilities amounts to $22 billion to $31 billion dollars annually. That may sound like a lot, but it's less than half of what the world spends on ice cream—$65.8 billion in 2020—and a tiny fraction of the price the world has paid over the past year for its failure to invest in the ecological foundations of human health.