Intact rainforests may be one of our greatest defenses against disease outbreaks such as Covid-19. A recent study published in the journal Forests reveals the potential health impacts of intensifying fires in the Amazon.

In the summer of 2019, newspaper headlines screamed, “The Earth’s Lungs are on Fire.” The title refers to forest fires that ravaged the Amazon rainforest, which produces a whopping 20% of the world’s atmospheric oxygen. But the fires endanger more than the planet’s lungs—they threaten our lungs.

Smoke from the 2019 Amazonian fires reached the city of Sao Paulo, located almost 2000 miles away from the Amazon (Source: NPR).

The health risks of Amazonian fires are global in scale, but the Amazon’s frontline communities feel them most acutely. Take the example of Apyterewa Indigenous Land, an area that witnessed the second highest deforestation rates across Amazonian Indigenous communities in 2019.

Researchers first looked at the biggest driver of forest fires in Apyterewa: deforestation. They then investigated particulate matter, small particles and liquid droplets in the air. Ash, smoke, and haze from forest fires are associated with high levels of particulate matter, which when inhaled can severely damage the heart and lungs.

Using spatial and image-based analysis, the researchers found that forested areas covered 92.4% of Apyterewa Indigenous Land in 2019—a slight drop from 95.2% in 2016. In the same time period, the percentage of total land used for human activity rose by 3%. This increase corresponds with growing deforestation rates for cattle ranching and agriculture.

Apyterewa Indigenous Land is located in the north-east sector of the Xingu region. The five most deforested Indigenous Lands in the Amazon are found in the Xingu district (Source: Socioambiental)

The spike in deforestation does not come as a surprise. In 2012, an update to the Brazilian Forest Code shrunk the mandatory percentage of legally protected reserves on privately owned land in the Amazon. That put more than 15 million hectares of forest, a landmass the size of Maine, under imminent threat. Environmental deregulation has propelled cattle ranchers to purchase and clear large tracts of old-growth forest, particularly in areas where land is cheap, such as the Apyterewa Indigenous Land.

The Parakanã people, the Indigenous group of Apyterewa, are especially vulnerable to land grabbing. A weak property rights regime and limited access to legal services prevent them from countering illegal incursions.

Deforestation imposes other—more invisible—costs on Indigenous people. The upswing in land clearing has had staggering effects on the particulate pollution emitted by deforestation-induced forest fires. Average annual levels of particulate matter increased by 58% between 2004 and 2019. Rising levels of particulate pollution contribute to degrading air quality in the rainforest, the study adds.

These jarring results strike an uncomfortable chord in our new, pandemic-driven world. According to Dr. Aron Bernstein, the interim director of the Center for Climate, Health, and the Global Environment, “there’s evidence that even short-term exposure to poor air quality [such as that caused by haze from forest fires] could make us vulnerable to respiratory infections,” including diseases like Covid-19.

With more than 5.5 million coronavirus cases, Brazil currently has the third highest number of cases worldwide. And the death rate among Amazon’s Indigenous people is nearly double that of the rest of Brazil. Harvey Fineberg, a doctor and the president of the Gordon and Betty Moore Foundation, notes that the links between forest related air pollution and disease spread need further investigation but underlined that “the directionality [of higher pollution levels and faster disease transmission] is pretty clear.”

Not all is dire; experts point to clear ways out of the crisis. First, to curb deforestation, the Brazilian government should reinstate the original Brazilian Forest Code. More robust monitoring and enforcement procedures are required to ensure compliance with this environmental regulation. Economic policies should also elevate the value of standing forest above deforested land. However, it is not enough to simply control deforestation. Initiatives that actively promote forest regrowth are necessary to restore a rainforest that once brimmed with plant and animal life.

Given the interlocking environmental and health crises we are faced with, these steps may produce a “dilution effect” wherein greater biodiversity mitigates the risk of virus transmission. Because forest loss itself creates optimal conditions for the spread of pathogens, a healthy ecosystem serves as a powerful protective barricade, and the loss of one, a deadly virus hotspot. To fortify our natural barriers, large-scale fires must be extinguished before they ignite widespread health damage.

The Amazonian fires last summer sent shock waves around the world, triggering visceral responses of horror and loss. Less visible, however, are the lingering effects of this tragedy: air pollution, poisoned communities, and strengthened disease vectors. The importance of an existing, breathing rainforest is no more clear than in the present, with the escalating number of Covid-19 cases worldwide and the apocalyptic state of affairs the pandemic has plunged us into. Preventing the wholesale destruction of the rainforest is our first line of defense against future pandemics. For the sake of our health, we need to rally for the Amazon.