Inside the world’s tropical forests, there are the agents of disease that have the power to bring our way of life to a halt. How we learn to live with these forests will determine our fate, hastening or slowing the onset of future pandemics and the climate crisis. BBC Travel and Future Planet explore two sides of our relationship with forests in two stories; this story is the first, and you can read the second here.

Levi Sucre Romero remembers hearing the news back in January about a novel coronavirus infecting people in China. “I honestly didn’t believe it would make it this far,” he said. “I felt like it was really far away.”

A member and leader of the Bribri, one of Costa Rica’s largest indigenous groups, Romero lives in Talamanca, a remote, mountainous region in the south of the country full of meandering rivers, dense jungle canopies and a near-constant drizzle of warm rain. Though the thatched-roof wooden homes of Talamanca Bribri, the group’s territory, are far removed from the country’s popular tourist hubs, Romero soon realised that it was only a matter of time until the virus reached them.

Romero also realised something else: the virus, he believes, was unleashed by human greed and ill treatment of the planet. “We’re unbalancing the habitat of species, we’re cutting down trees, we’re planting monocultures, we’re filling the world with cities and asphalt and we’re using too many chemicals,” Romero said. “It’s a cocktail of bad practices.”

Like Sars and Mers, two other recent, deadly coronaviruses, Covid-19 is a zoonotic disease that came from an animal. Evidence points to its likely origin in a bat, followed by a potential crossover into an intermediary species – possibly a pangolin – before transmission into humans at a wet market in Wuhan, China. While Covid-19’s exact origins have yet to be pinpointed, overwhelming research shows that deforestation and commercial wildlife trade heighten the risk of zoonotic diseases that can potentially cause pandemics. And according to Romero, both are human activities that entail the destruction of nature.

“My people have cultural knowledge that says when Sibö, our God, created Earth, he locked up some bad spirits,” Romero said. “These spirits come out when we’re not respecting nature and living together.”

Romero coordinates the Mesoamerican Alliance of People and Forests, one of the most important land-rights platforms for indigenous communities in Central America and Mexico, which represents more than 50,000 people who live in the most densely forested lands in the region. He knows for a fact that there is another, more sustainable and respectful way to live in relation to the Earth – because the Bribri and many other indigenous groups around the world practice it.

I do not believe this will be the last pandemic of this type

For years, Romero and other indigenous leaders have been urging the rest of the world to adopt a more indigenous-inspired way of coexisting with nature, including leaving habitats intact, harvesting plants and animals at sustainable levels and acknowledging and respecting the connection between human and planetary health. Now, they are reiterating that message in light of the coronavirus.

At a March panel sponsored by the global journalism initiative Covering Climate Now in New York City, held days before the city shut down and later became the global epicentre of the worldwide pandemic, Romero and other indigenous leaders from Brazil and Indonesia emphasised the role that traditional knowledge, practices and land stewardship can play in protecting the planet. These protections, they said, extend not just to lessening climate change and biodiversity loss, but to reducing the risk of future pandemics.

“We are convinced that this pandemic is the result of a wrong use of natural resources and a wrong way of living together with these resources,” Romero said. “I do not believe this will be the last pandemic of this type.”

A wealth of research supports the link between novel disease emergence and environmental destruction. Many viruses naturally occur in animal species, and deforestation increases the odds of people coming into contact with an animal carrying a virus that is new to humanity, potentially resulting in a spill-over event. A 2017 Nature Communications paper revealed that emerging zoonotic disease risk is highest in tropical forests that are experiencing land-use changes, including from logging, mining, dam building and road development. As the authors report, such activities carry an intrinsic risk of disease emergence because they disrupt ecological dynamics and increase contact between humans, livestock and wildlife.

“It’s a stochastic process,” said Erin Mordecai, a biologist at Stanford University. “It’s driven by chance encounters between particular people and particular animals, and what pathogens they’re carrying at that time.”

Deforestation can also spread existing diseases. In October, Mordecai and co-author Andrew MacDonald reported in the Proceedings of the National Academy of Sciences that an increase in deforestation in Brazil tends to increase the rate of malaria transmission, with about six-and-a-half new cases occurring per square kilometre of cut-down forest. The reason, they believe, is that cutting trees creates more forest edge – the favourite breeding habitat for Brazil’s malaria-transmitting mosquitoes. Development in frontier regions also brings more people closer to the forest and draws pioneers in from other parts of the country who have never been exposed to malaria and thus have no resistance.

Deforestation tends to lead to these opportunities in which species that don’t normally come into contact are coming into contact

While every disease is different, the general pattern, Mordecai told me, is that deforestation disrupts ecosystems and creates edge habitats hovering between domesticated and wild, in which the human and natural world overlap. “Deforestation tends to lead to these opportunities in which species that don’t normally come into contact are coming into contact,” she said. “That creates opportunities for pathogens to spill over.”

Studies reveal that the both legal and illegal commercial wildlife trade also increase the risk of new diseases emerging by subjecting wild animals to stressful, unhygienic conditions. Still-living species are often mixed together, allowing them to exchange viruses. Trade also often takes place in urban centres, where many people may come into contact with the animals – and with each other – further encouraging a new disease’s spread.

The wildlife trade itself is also linked to deforestation. Hunters and poachers tend to access wilderness areas through roads. As formerly remote areas are opened up by new transportation corridors, wildlife trade tends to follow.

Medical experts and conservationists have been warning of the health risks posed by both deforestation and wildlife trade for decades, but to no avail. In 2003, for example, China briefly banned wildlife trade in response to Sars, but business resumed within a year and has only grown since.

As land stewards, many indigenous groups help to guard against these threats. “By protecting indigenous landscapes, you’re protecting not only those people and their way of life, but also preventing really rapid transformation of landscapes,” Mordecai said. “That rapid transformation has huge-scale cultural and environmental consequences, but also disease-transmission consequences.”

A large number of indigenous groups live in tropical forests – precisely the landscapes with the highest risk for new disease emergence, and also the places facing the highest rates of deforestation. Tropical deforestation is accelerating and accounts for about 90% of total deforestation worldwide. A 2020 study reported that at least 36% of the world’s remaining intact forests – half of which are located in the tropics – fall within indigenous lands.

Of course, indigenous people are extremely diverse. Some live in cities, others in forests; some extract resources for profit, others use nature only for subsistence. In general, though, indigenous groups “are much more effective at protecting the forest and environment on their lands than most other users,” said Mary Menton, a research fellow in environmental justice at the University of Sussex. In certain parts of Brazil, for example, indigenous protection is visible in satellite images from space.

“You can see exactly where the lines of indigenous territories are,” Menton said. “Deforestation eats into forests around where indigenous areas are, and those areas really act as an effective barrier for expansion.”

Indigenous people’s lands, by and large, tend to be much better protected than other areas of the forest

This is also supported by scientific evidence. A 2012 study comparing 40 protected areas and 33 community-managed forests revealed that the community-managed areas suffered less deforestation. “If we look across the tropics, indigenous people’s lands, by and large, tend to be much better protected than other areas of the forest, even comparing community and indigenous lands to protected areas,” Menton said.

Practically speaking, this is partly because indigenous people tend to live on large areas of land with relatively small populations. But even groups that live in smaller tracts of forest in north-east Brazil, for example, live more sustainably than much of the rest of humanity. “It’s not just that they have lots of forest, it’s the way they treat and see the forest, and interact with it,” Menton said.

Many groups have been living in forested areas for generations and view the landscape as part of their community. Some also believe that their ancestors are part of the forest. Protecting nature, therefore, isn’t just about ecology and biodiversity, Menton says, but also about preserving lives, history and culture.

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Indigenous people accomplish this through a variety of means that largely boil down to having a respect and awareness of the effect they have on the forest, Menton said. The Bribri, for example, divide their land into family and community areas, each of which have internal rules designed to promote sustainability. For example, members of the community can cut as many leaves as they want from local suita palms – used to make everything from houses to brooms – so long as they leave at least five leaves on each harvested plant so it can produce more leaves.

We need to rethink the model of development that’s based on accumulating wealth while destroying resources

Many indigenous people also do not treat the forest as a means or impediment to getting rich. Romero, for his part, thinks that hyper-globalisation and consumerism are at the heart of many of the world’s ills. “We need to rethink the model of development that’s based on accumulating wealth while destroying resources,” Romero said. “I see an economic model that is predatory to resources and to nature, that causes a lack of balance in the world.”

However, profit-driven companies, governments and individuals often view indigenous people as standing in the way of economic growth. Around the world, indigenous land rights are under attack by agriculture, mining and other extractive industries. Between 2002 and 2017, Menton found that more than 1,500 environmental defenders were murdered in 50 countries, and that indigenous peoples died in higher numbers than any other group on the list. In 2015 and 2016, for example, indigenous people represented 40% of all murdered environmental defenders. A report published in April 2020 by the Pastoral Land Commission, a non-profit organisation in Brazil, likewise revealed that one-third of all families who faced land conflicts in rural Brazil in 2019 were indigenous.

Menton adds that indigenous people face additional threats because of racism and “perceptions that they’re second-class citizens”. Often, this is a problem promoted from the top down. Brazil’s president, Jair Bolsonaro, recently said, for example, that “Indians are evolving” to become “increasingly human, like us”. Indigenous people, in other words, are “facing threats both in terms of actual physical conflicts over land, but also cultural threats and attacks over their right to exist,” Menton said.

Attacks on indigenous rights are not just attacks on individual cultures, Romero says, but on the health of the planet as a whole. “When we have rights over our forests and our lands, that means survival for us, for our families,” he said. “But it also means we have a better probability of avoiding pandemics.”

The Bribri, like much of the world, are now on lockdown. “The rhythm of our lives has been cut short,” he said. Visits with elders are no longer permitted, sales of produce to the national market have dropped by around 90%, and the group’s cultural and ecological tourism efforts – including guided trips to mountains and rivers, traditional food tours and home stays on family ranches – have stopped as well. “I could go on and on. There’s a lot of impacts,” Romero said.

Once the world does emerge from Covid-19, Romero hopes that there will be a silver lining to all of the suffering, loss and hardship that it has caused. He hopes that people will be more receptive to the knowledge that he and other indigenous leaders have to offer, and that humanity will begin to re-evaluate its relationship with nature.

“I think we have a long way to go, but after the coronavirus, I have faith that this will open up some space with governments,” Romero said. “After this pandemic, governments should listen more.”

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