In 1998, pigs in a farm in northern Malaysia developed a respiratory disease, marked by very loud coughing. Some of the animals had no other symptoms, others had fevers and muscle spasms, but most recovered. Then the previously unknown disease jumped to farmworkers and became more virulent — 265 people developed severe encephalitis, and 105 of those died, a death rate comparable to Ebola.
Medical investigators found that the farm where the epidemic started kept some 30,000 pigs in open-air pens near mango trees. Fruit bats from the deep forests of nearby Borneo had recently migrated to those trees when their natural habitats were bulldozed to make way for palm plantations, and the pigs ate partially eaten fruit that the bats dropped. The bats’ saliva carried a then-unknown virus — later named Nipah after a nearby village — that was harmless to them but made pigs sick and killed people. The Malaysian outbreak was contained by killing over a million pigs, but, having escaped its forest origin, the virus moved on: Nipah is now endemic in Bangladesh and parts of India, where yearly outbreaks still kill 40% to 75% of those infected. There is no vaccine and no cure.
The forest clearing that destroyed the bats’ natural habitat was not a new or isolated development. Indeed, as Karl Marx wrote, “the development of civilization and industry in general has always shown itself so active in the destruction of forests that everything that has been done for their conservation and production is completely insignificant in comparison.”1
After the last ice age and before the invention of agriculture, forests covered roughly six billion hectares of Earth’s habitable land surface. Today the forested area is just four billion hectares, a 33 percent decline in about ten thousand years. But over half of the decline occurred after 1900, and most of that has occurred since 1950.2
In Earth System science, both the Great Acceleration graphs and the Planetary Boundaries project include loss of tropical forests as key developments in the global shift from relatively stable Holocene conditions to the more volatile Anthropocene in the mid-twentieth century.3 The 2023 update to the Planetary Boundaries framework concluded that land system change entered the danger zone in about 1988, and has “since been transgressed into a zone of increasing risk of systemic disruption.”4
In his history of deforestation, Michael Williams describes the period since 1945 as the Great Onslaught.
“The cataclysmic events of World War II altered the world’s forests more surely than any “end of the century” of about 50 years before. But it was not the five years of conflict, devastating as they were, that caused deforestation; rather, it was the aftermath of change that they unleashed that was rapid, far-reaching, and caused a disruption of global biomes. The nature and intensity of change reached worrisome levels of pace, magnitude, and environmental significance compared to anything that had gone before.”5
It is sometimes claimed that deforestation is caused by high birth rates in tropical countries — that too many poor people are carving small farms out of tropical forests, to feed their families. In fact, while state-sponsored colonization of peasant farming was an important factor in forest removal in Latin America and southeast Asia until about 1980, “the majority of global deforestation today is driven by multinational corporations, including Cargill, JBS and Mafrig, as well as their creditors BlackRock, JPMorgan Chase and HSBC.”6 Agribusiness giants clear immense areas to produce monocrop commodities for global markets. Just four products — beef, soy, palm oil, and wood — are responsible for over 70% of twenty-first century deforestation7 and the cleared areas are being replaced not by family farms but by massive ranches and plantations.
Environmentalists have justifiably focused attention on the links between deforestation and climate change — it’s estimated that land use change is responsible for 15% of greenhouse gas emissions. That is, of course, a critically important issue, but as socialist epidemiologist Rob Wallace points out, we also need to understand and challenge the role of investors based in London, New York, and Hong Kong who are turning tropical forests into breeding grounds for global pandemics.
“Capital is spearheading land grabs into the last of primary forest and smallholder farmland worldwide. These investments drive the deforestation and development leading to disease emergence. The functional diversity and complexity these huge tracts of land represent are being streamlined in such a way that previously boxed-in pathogens are spilling over into local livestock and human communities.”8
The vast pool of biodiversity in tropical forests includes uncounted viruses that have inhabited and adapted to “reservoir species,” through millions of years of evolution. The massive disruption and degradation of forests increases contact between humans and their domestic animals on one hand, and wild animals on the other — contacts that create new opportunities for viruses and bacteria to infect previously unknown hosts. As Andreas Malm writes, deforestation is a major driver of zoonotic spillover and emerging infectious diseases.
“That strange new diseases should emerge from the wild is, in a manner of speaking, logical: beyond human dominion is where unknown pathogens reside. But that realm could be left in some peace. If it weren’t for weren’t for the economy operated by humans constantly assailing the wild, encroaching upon it, tearing into it, chopping it up, destroying it with a zeal bordering on lust for extermination, these things wouldn’t happen ….
“Deforestation is an engine not only of biodiversity loss, but of zoonotic spillover itself. When roads are cut through tropical forests, patches cleared, outposts placed deeper in the interior, humans come in contact with all the teeming life forms hitherto left on their own. People raid or occupy spaces where pathogens dwell in the greatest plenitude. The two parties stage their most frequent encounters along the edges of fragmented forests, where the contents of the woods can slip out and meet the extremities of the human economy; and, as it happens, generalists like mice and mosquitos, with a knack for serving as ‘bridge hosts,’ tend to flourish in those zones….
“The hotspots of spillover are the hotspots of deforestation.”9
“As a result,” Wallace writes, “forest disease dynamics, the pathogens’ primeval sources, are no longer constrained to the hinterlands alone. Their associated epidemiologies have themselves turned relational, felt across time and space. A SARS can suddenly find itself spilling over into humans in the big city only a few days out of its bat cave.”10
In addition to creating new opportunities for virus spillover, deforestation provides expanded habitats for vectors — the mosquitoes and other insects that carry pathogens from infected animals to humans. A report published by the United Nations Environment Program, the World Health Organization and the Convention on Biological Diversity warns:
“Changes to habitats, including through altered species composition (influenced by conditions that may more favorably support carriers of disease, as seen with malaria-harboring vectors in cleared areas of the Amazon) and/or abundance in an ecosystem (and thus potential pathogen dispersion and prevalence), and the establishment of new opportunities for disease transmission in a given habitat, have major implications for health. Human-mediated changes to landscapes are accompanied by human encroachment into formerly pristine habitats, often also accompanied by the introduction of domestic animal species, enabling new types of interactions among species and thus novel pathogen transmission opportunities.”11
Heavy use of pesticides sharply reduced the incidence of insect-carried diseases in the last half of the twentieth century, but they have since returned with a vengeance. The most deadly, malaria, kills between one and three million people every year, mainly in sub-Saharan Africa. The insects that carry it and other pathogens find attractive breeding grounds in recently deforested areas.
It’s sometimes claimed that palm tree plantations should be viewed as effective replacements for original forests, but scientific studies show both that “mosquito vectors of human disease are disproportionately represented in deforested habitats,” and that there is “a positive association between the number of vector-borne disease outbreaks and the increase in land areas converted to oil palm plantations.”12
As this shows, forests are not just trees — they are immensely complex ecosystems whose ecological functions cannot be duplicated simply by introducing other, more profitable, trees. One of those functions is limiting the spread of vector-borne diseases and viral spillover. As Roderick Wallace and his associates argue, to be truly sustainable, policies and actions must prioritize “preserving what the forest does, as opposed to what it is.”13
[To be continued]
Source >> Climate & Capitalism
References
- Karl Marx, Capital: A Critique of Political Economy. Vol. 2, trans. David Fernbach, vol. 2, The Pelican Marx Library (London: Penguin Books in association with New Left Review, 1985), 322. ↩︎
- Omri Wallach and Aboulazm, Zach, “Visualizing the World’s Loss of Forests Since the Ice-Age,” Visual Capitalist, April 1, 2022. ↩︎
- Ian Angus, Facing the Anthropocene: Fossil Capitalism and the Crisis of the Earth System (New York: Monthly Review Press, 2016), 44–45, 71–77. ↩︎
- Katherine Richardson et al., “Earth beyond Six of Nine Planetary Boundaries,” Science Advances 9, no. 37 (September 15, 2023). ↩︎
- Michael Williams, Deforesting the Earth: From Prehistory to Global Crisis: An Abridgment (Chicago: University of Chicago Press, 2006), 395. ↩︎
- April Fisher, “Deforestation and Monoculture Farming Spread COVID-19 and Other Diseases,” Truthout, May 12, 2020. ↩︎
- Hannah Ritchie and Max Roser, “Cutting down Forests: What Are the Drivers of Deforestation?,” Our World in Data, March 18, 2024. ↩︎
- Robert G. Wallace, Dead Epidemiologists: On the Origins of COVID-19 (New York: Monthly Review Press, 2020), 30–31. ↩︎
- Andreas Malm, Corona, Climate, Chronic Emergency: War Communism in the Twenty-First Century (London New York: Verso, 2020), 35, 42, 43. ↩︎
- Rob Wallace et al., “COVID-19 and Circuits of Capital,” Monthly Review 72, no. 1 (May 1, 2020): 1–15. ↩︎
- World Health Organization and Convention on Biological Diversity, Connecting Global Priorities: Biodiversity and Human Health. S State of Knowledge Review (Geneva: World Health Organization, 2015), 39. ↩︎
- Nathan D. Burkett-Cadena and Amy Y. Vittor, “Deforestation and Vector-Borne Disease: Forest Conversion Favors Important Mosquito Vectors of Human Pathogens,” Basic and Applied Ecology 26 (February 2018): 101–10; Serge Morand and Claire Lajaunie, “Outbreaks of Vector-Borne and Zoonotic Diseases Are Associated With Changes in Forest Cover and Oil Palm Expansion at Global Scale,” Frontiers in Veterinary Science 8 (March 24, 2021): 661063. ↩︎
- Rodrick Wallace et al., Clear-Cutting Disease Control: Capital-Led Deforestation, Public Health Austerity, and Vector-Borne Infection (Cham: Springer International Publishing, 2018), 55. ↩︎