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Hypothesising on the emergence of SARS-CoV-2 through bats: Its relation to intensive pig-factory farming and the agro-industrial complex

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Abstract

The emergence of SARS-CoV-2 and the resulting disease, COVID-19, is possibly related to bats, which have been shown to be a reservoir for many kinds of viruses, including coronaviridae, due to their physiological peculiarities. However, it remains controversial how, if at all, the virus evolved from bats to become infectious to humans, turning the resulting disease into a pandemic. The current discussion is based on some facts around the agro-industrial complex, such as intensive pig-factory farming in the city of Wuhan and its surroundings. A putative triangular relationship between bats, pigs and humans is described as a striking fictional story first, serving to illustrate the hypothesis. Then the history of current globalised animal farming from its beginnings during the 'Green Revolution' and its detrimental impacts are summarised. With COVID-19 research in its infancy, this is followed by mappings of pig-factory farming in the state of Santa Catarina, in the south region of Brazil and outbreaks of COVID-19 in humans. The triangle hypothesis, if proven true, might add risks to the pandemic, if factory animal farming remains in its current form. The authors recommend more sustainable farming practices within a framework of degrowth.
Discussion Paper
Copyright © is with the authors. 1
Hypothesising on the emergence of SARS-CoV-2 through bats: Its relation to
intensive pig-factory farming and the agro-industrial complex
Immo Fiebrig • Larissa Bombardi • Pablo Nepomuceno
Abstract
The emergence of SARS-CoV-2 and the
resulting disease, COVID-19, is possibly related
to bats, which have been shown to be a
reservoir for many kinds of viruses, including
coronaviridae, due to their physiological
peculiarities. However, it remains controversial
how, if at all, the virus evolved from bats to
become infectious to humans, turning the
resulting disease into a pandemic. The current
discussion is based on some facts around the
agro-industrial complex, such as intensive pig-
factory farming in the city of Wuhan and its
surroundings. A putative triangular
relationship between bats, pigs and humans is
described as a striking fictional story first,
serving to illustrate the hypothesis. Then the
history of current globalised animal farming
from its beginnings during the 'Green
Revolution' and its detrimental impacts are
summarised. With COVID-19 research in its
infancy, this is followed by mappings of pig-
factory farming in the state of Santa Catarina,
in the south region of Brazil and outbreaks of
COVID-19 in humans. The triangle hypothesis,
if proven true, might add risks to the
pandemic, if factory animal farming remains in
its current form. The authors recommend
more sustainable farming practices within a
framework of degrowth.
Dr. Immo Fiebrig ()
Honoarary Associate Professor, NCMH, School
of Biosciences, University of Nottingham,
Sutton Bonington Campus, LE12 5RD Sutton
Bonington,
e-mail: immo.fiebrig@nottingham.ac.uk
Dr. Larissa Bombardi
Professor at Department of Geography,
University of São Paulo, Av Professor Lineu
Prestes, 338 Cidade Universitária - São Paulo -
SP 05508-000;
e-mail: larissab@usp.br
Dr. Pablo Luiz Maia Nepomuceno
Department of Geography, University of São
Paulo, Av Professor Lineu Prestes, 338
Cidade Universitária - São Paulo - SP 05508-
000; e-mail: pablo.nepomuceno@usp.br
Introduction
The increase in food production after World
War II led to intensifying agriculture, with the
factory farming of animals, mostly beef, pork
and chicken, as a means of mass production of
affordable meat. At the time, the related
technologies were largely developed in the
USA and later transferred to many other parts
of the world, including Europe, Brazil and
China amongst others. Whether this kind of
meat mass production is actually called
intensive animal husbandry or mass livestock
farming is essentially irrelevant. The essence
of this kind of meat production is the lack of
ethics and the absence of compassion for the
species-specific needs of the animals, which
are raised in the confined and contaminated
spaces of factory hangars. The animals
become highly and chronically stressed and
thus immuno-depressed, more susceptible to
the epidemic spread of infectious diseases. In
addition, their excreta pose detrimental risks
to the environment.
Due to a variety of restrictions, including travel
and research opportunities, the authors
merely speculate about the evolution of
Discussion Paper
Copyright © is with the authors. 2
COVID-19 in or around Wuhan, China. They
propose no direct connection to any alleged
‘artificial engineering’ by any putatively
‘devious’ research laboratory.
The first tentative evidence points towards a
correlation between outbreaks of COVID-19 in
humans in locations of intensive pig farming in
the state of Santa Catarina in Southern Brazil.
An infectious cycle via SARS-CoV-2 may be
created through streams of untreated
excrement entering water bodies and infecting
potable water consumed by humans. Another
means of infection from pig to human could
be via farm managing staff or staff working in
slaughterhouses. Before we move to facts, we
present a brief fiction on virus evolution:
Ping-Pong-Pang! SARS-CoV-2, a spiky ball
linking a nauseous threesome.
Donald Trump is pointing his finger at China. In
his narcissistic quest for re-election, he
accuses the People´s Republic of being guilty
of launching a deadly pandemic. People
believing his potshot might, however, be
unable to see the wood for the trees. Within
only a few months, the corona virus has
unleashed a global health and economic
avalanche.
US intelligence services have allegedly been
engaged to prove that the frenzied virus had
been engineered from infected bats in a
Wuhan research laboratory. And, as is being
argued, viral material escaped from the lab
due to ignorance and negligence. Others still
believe the source is to be traced back to
Wuhan´s peculiar wet markets selling pitiably
caged pangolins or fried bats on a stick,
amongst other wildlife meat. Both the US´s
and China´s propaganda is probably good at
identifying scapegoats and at igniting smoke
grenades. Evidence shall surface in due course
– once the smoke dissolves.
To set the scene: In pointing his forefinger at Xi
Jinping and Beijing´s bureaucrats, Trump
might, unwittingly – with his other three
fingers – be pointing back at himself and his
America. Finger one: agrochemicals - that is,
synthetic pesticides and fertilisers, but also
antibiotics and other so-called pharmaceutical
feed additives. Finger two: genetically
modified organisms like GMO soya and GMO
maize. Finger three: intensive mass animal
farming, for example, pork.
This is an attempt to shed a little light into the
darkness by joining dots. The truth may
indeed contain a part of Wuhan, a bit of
laboratory and an essence of bat, but
arranged differently. From a humble view as
natural scientists, we should not be looking at
a single unfortunate or vile event. We need to
think in systems, in population dynamics and
in evolutionary processes. What does this
mean? Heads up! Let us switch to a dystopian
storyline resembling Aldous Huxley´s famous
novel, ‘Brave New World’.
Joining the dots of a macabre plot the story
unfolds as follows: Hubei as a province in
central China and Wuhan as its capital are
known for their immense industrial mass
production of factory pork meat. For example,
Globalmeatnews.com
1
states 14 large
breeding companies having a joint annual
production of 1.5 million pigs in 2018 in Hubei
alone. Assuming Wuhan is a place where
millions of pigs are raised in massive hangars,
this means at least tens of thousands of
animals are being held as prisoners in confined
spaces per production unit at any time.
These creatures, literally reduced to pork
meat-producing machines, suffer as we would
suffer under such conditions. They are anxious,
they are bored, they are in pain and hugely
stressed and as such they are fed to grow until
killed. During their time of imprisonment, the
immune system has weakened significantly. To
survive, they need to be given antibiotics,
painkillers and hormones, as well as other
drugs we may not even know of. Then they will
be shooed to the slaughterhouse. Fat and
barely alive. But before this happens, the next
player comes into the scene. Bats, or
‘microchiroptera’ in scientific terms.
Driven out of their receding habitats around a
growing Wuhan metropolis, bats are
Discussion Paper
Copyright © is with the authors. 3
desperate to find food and shelter. It will not
take long before they discover both. In
Wuhan´s thriving pork factories. Under a
ceiling, safe from their usual predators and
weather events, bats are free to share the
protein-rich soy pellet diet of their inmates.
And the bats proliferate. They operate at
night, such that their scavenging activities
may not appear too disturbing, while sleeping
during the day, silently dangling from the
ceilings of their new habitats.
Bats are natural carriers of corona viruses –
amongst many other viruses. In the present
narrative, this is taken as a proven fact. Bats
echolocate, meaning they see with sound.
Some do this by contracting their voice box
(larynx), others click their tongues propagating
sound – and probably viruses – through mouth
and nostrils as they fly. Picture this: They are
airborne, fluttering around freely in swine
factories. They are constantly echolocating in a
hot, humid and stuffy environment to avoid
crashing with fellow bats in their common
airspace whilst locating the feedlots. In doing
so, they might assiduously be spraying corona
viruses over immune-depressed and
defenceless mammals, again and again.
Only a year ago in April 2019, China reported
an untreatable virus decimating their pork
meat production, allegedly from African swine
fever virus infection
2
. What if instead it could
have been an emerging strain of
coronaviridae, mutated and becoming
increasingly infective to immune-depressed
factory animals?
To summarise a hypothesis: Wuhan´s swine
factories were the actual laboratories of a
huge epidemiological experiment –
uncontrolled of course. The plot constituting a
ping-pong game that went on for months or
even years, unnoticed and unintentionally in a
friendly bat-pork relationship. A ping-pong
game taking place zillions of times, until a
corona virus similar to SARS-CoV-2 evolved
enough to become successfully adapted, that
is, highly virulent within a new species.
From this bat-swine-ping-pong hypothesis, the
narrative from swine to humans can be
developed in various directions. Pigs and
humans have similar digestive systems. The
biochemistry of their glycoproteins in the
protective linings of, for example throat, nose,
bronchia, lungs or gut, are much like humans.
With mucosal tissue being the usual gate to
hijacking the next body, corona might have
found the necessary akin conditions in man.
Combined, diseased pigs could have passed
SARS-CoV-2 or its precursor strain to farm
workers, who in turn passed it on to their
family’s local community. However, it is much
more likely that meat from diseased animals
entered the food chain and infected many
more people. Maybe those pigs which died
before getting to the slaughterhouse had been
sold illegally on a black market, where
anything would be possible. In another
scenario, the bat populations feeding on pork
food might, like a pest, get out of hand. Farm
staff would organise bat hunts regularly to
keep some control over populations. The
reward gets cashed in. And the bats carrying a
corona virus strain dangerous to pigs, end up
on a frying stick on Wuhan´s wet market,
infecting humans before reaching the hot oil.
And not to forget, there is also a massive
stream of pig faeces, probably drenching the
environment in a more-or-less uncontrolled
manner. It might be contaminating the
drinking water of humans and pigs alike.
Whichever way, ping-pong-pang, an epidemic
gets born!
Let us now switch from the above narrative,
which is rather more like science fiction, to the
principles of industrialised agriculture and
some tentative evidence from mapping the
spread of COVID-19 in Santa Catarina amongst
humans on the one hand and the location of
pork factories on the other. The fictional
description, however, may in fact be more real
than we wish to imagine.
Discussion Paper
Copyright © is with the authors. 4
The triumphs of the Green Revolution
Modern industrial agriculture is more about
mass producing and trading commodities, less
about supplying the world´s population with
non-toxic, healthy and nutritious food.
In an attempt to understand the logic of
intensive farming of pigs and other farm
animals, we have to explain the system of the
so-called 'Green Revolution'. It is a term given
to the process of 'technification' of agriculture
and it includes animal farming. In its
technification process, it employs synthetic
inputs, that is, chemical raw materials like
fertilisers, pesticides, antibiotics and
hormones as well as industrialised feed,
modified seeds and high-tech agricultural
machinery, amongst others. The Green
Revolution became established in the period
after World War II and from an economic
point of view, it industrialised any agricultural
and pastoral activities that had previously
predominantly been conducted by peasants
on a small scale. The aim was to become more
productive, provide food, and above all meat,
more cheaply.
The model for the industrialisation of
agriculture presupposes the standardisation of
many inputs and processes: seeds, vegetative
cycles of plants and crops are standardised
through 'genetic improvement'; growth is
additionally standardised by remote control of
the pH, moisture content and nutrients of the
soil together with control of 'pests'. There is
also a standardisation in the growth of meat-
producing animals and, whenever possible, a
reduction of the production cycle, whether for
plants or animals – faster growth is better
3
.
This industrialisation of agriculture is a global
phenomenon. It has a worldwide dimension as
does the economy itself. Multi-national
companies producing the agro-chemicals
needed for these artificial forms of agriculture
and livestock farming are increasingly
organising themselves in an oligopolistic
manner. Capital concentration is achieved
through mergers and acquisitions where, for
example, the five largest companies in the
sector control 70 % of worldwide sales of
pesticides
4
.
These enterprises are headquartered in the
Global North, primarily in the United States
and the European Union. However, a
significant part of their sales is aimed at the
Global South, particularly Latin America with
its extensive, forest-consuming monocultures
of soya and maize for example, which is the
basis for producing feed for confined animals.
Nowadays, there is not only a worldwide trade
in cereals and meat, but both product groups
are also traded on the stock exchanges,
shifting their purpose from goods for resale
for human provisioning into an item of
speculation. As such, we have a combined and
orchestrated movement: on the one hand, the
chemical industry ‘sustains’ agriculture on an
industrial scale; on the other, the stock
exchanges allow the international commerce
of food crops, converting them into
commodities.
Cattle, chickens and pigs as a commodity have
to fulfil the following requirements: their meat
must be stored whilst not losing its nutritional
characteristics, it must be internationally
standardised, and as such it can be traded on
the stock market.
The transformation of farm animals into mere
merchandise, void of any compassion for their
fate, has been achieved by this industrial
process of farming. As has been said before,
such animals are bred in a confined manner,
non-appropriate for any species, with no
access to the soil, to sunlight, or to a place
where they can move around freely. They are
crammed into tiny cubicles that prevent them
from exercising their most basic habits:
grazing, foraging or wallowing.
Globalisation´s catch from China to Brazil
From Wuhan´s putative deadly triangle and
global commodity farming for the stock
market we shall move to Brazil’s daily reality,
where immense amounts of forest are
Discussion Paper
Copyright © is with the authors. 5
destroyed to cultivate soy and corn
monocultures.
China is the world’s leader in pork production,
with around 310 million pigs – more than
twice the stock of the European Union, which
takes second place in the ranking with around
148 million pigs. The United States occupies
third place with around 78 million pigs,
followed by Brazil in fourth place with 37
million. Today, Brazil is the world’s largest
exporter of beef and chicken, as well as the
fourth largest exporter of pork.
In Brazil, pork production is concentrated in
the southern region of the country, providing
about 66% of the national production. Santa
Catarina is the state that produces most of this
pork and is responsible for more than 25% of
the total production in Brazil. More than half
of the pork exported from Brazil originates in
Santa Catarina, which produced more than a
million tonnes of this meat in 2018.
This pork production in Brazil is mostly
intensive: more than 70% of the animals are
raised in a confined way. Such animals are
basically given feed produced with two crops:
corn and soy. It is estimated that 345 kg of
feed is needed to produce a pig weighing
around 100 kg, the consumption of its
progenitors to be added
5
.
This production model has at least two quite
obvious and severe environmental impacts:
one, upstream of production and another,
downstream.
Upstream of pork production: so that the
animals can be fed, there are vast
monoculture areas of soy and corn that
advance over the Amazon and are responsible
not only for deforestation and burning, but
also for the contamination of this area with
pesticides. Today, in Brazil, there is an area the
equivalent of Germany which is cultivated
with soy (more than 90% of it is transgenic).
It is not a mere coincidence that China, which
is responsible for more than 50% of the
worldwide pork production, is today the main
consumer market for soy produced in Brazil.
Evidence from Santa Catarina´s pork industry
Downstream of pig husbandry, there is very
severe environmental contamination. In the
1980s, it was estimated that about 85% of the
water consumed in the rural area of Western
Santa Catarina, hotspot for pork production in
Brazil, was of unacceptable quality.
Currently, in this region, only 15% of the pigs’
manure follows adequate storage and
treatment protocols.
In addition to these serious socio-
environmental impacts, resulting from
intensive pig raising, we are possibly facing a
new problem related to this model.
The cruelty with which such objectified
animals are bred, together with genetically
modified (GM) feed, the concomitant use of
antibiotics and their overall unhealthy
environmental conditions, make them
immune-depressed, as has already been
described. They are perfect receptacles for the
development of viruses such as SARS-Cov-2.
In recent days, the press has reported that
there is a very large number of slaughterhouse
workers infected with SARS-Cov-2. Such
reports have been described for Germany, the
USA and, more recently, Brazil – but they are
probably not the only countries affected.
Mapping COVID-19 outbreaks versus
intensive pig farming
Analysing the distribution of people infected
by COVID-19 in Brazil spatially, particularly in
the state of Santa Catarina (Map 1) - the state
that produces the most pork in Brazil - we
surprisingly find support for the hypothesis
developed above.
Discussion Paper
Copyright © is with the authors. 6
Map 1 – COVID-19 – People infected in Santa Catarina – Brazil
There are essentially two main areas or
'hotspots' of coronavirus infections in this
state. One focus is along the coast. This is to
be expected, as this is the location of large
cities, where the industrial sector is
concentrated and the demographic density is
higher per se. Notably, there is another
affected area in the west, the focus that we
are highlighting.
Mapping the municipalities of Santa Catarina
with the highest COVID-19 infection rates
(Map 1) with those municipalities where there
is a high density of pig farming (Maps 2 and 3),
municipalities show a tendency to coincide.
Map 1 has been generated from the
processing of data on the amount of people
infected with SARS-CoV-2 leading to COVID-19
(made available by the Santa Catarina
Department of Health; SESSC, 2020)
6
.
Regarding Maps 2 and 3, agricultural
production data by municipality have been
used, according to the latest Brazilian
agricultural census conducted in 2017 (made
available by the Brazilian Institute of
Geography and Statistics; IBGE, 2017)
7
.
These data have been imported, processed,
classified and represented in the form of
thematic maps using the resources available in
the Geographic Information System (GIS)
software, QGIS (Quantum GIS 2.18.7),
according to the principles of thematic
cartography systematised by Bertin (1967)
8
,
Salitchev (1979)
9
and Simielli (2007)
10
.
The spatial correlation in this region is
surprising: there is an overlap between the
municipalities where there is a large number
of pigs per farm (Map 2) as well as pigs per
municipality (Map 3) in relation to those
municipalities where there is a greater
number of persons infected with COVID-19
(Map 1).
Discussion Paper
Copyright © is with the authors. 7
Map 2 – Quantity of pig per farms – Santa Catarina – Brazil
Map 3 – Quantity of pigs per municipality – Santa Catarina – Brazil
Discussion Paper
Copyright © is with the authors. 8
Issues presented for discussion
Could the SARS-CoV-2 strain have found a
global reservoir in the pigs we slaughter,
process and eat via the bat-pig-human triangle
in Wuhan? Might the pigs’ faeces be
contaminating the water that humans drink,
given that the virus survives in faeces?
In this discussion paper, we have proposed the
hypothesis of three species whose unnatural
habitats have come close enough and under
conditions to promote the evolution of a virus
which can be infectious to multiple species –
possibly including pets like cats and dogs or
other farm animal species like cattle and
chicken. Is this triangular hypothesis just
science fiction or a macabre and fateful reality
resulting from ruthless industrialisation of
agriculture?
Conclusions
We propose further research by, for example,
virologists, epidemiologists, veterinaries,
biologists and agro-ecologists in a joint effort
to get this pandemic under control, and to
avoid the emergence of new viruses with
similar potential by implementing a more
animal-friendly and environmentally
regenerative agriculture and animal
husbandry based on agro-ecological
principles.
References
1
https://www.globalmeatnews.com/Article/2018/07/05/Wuhan-pig-farms-to-organise-China-s-pork-
industry
2
https://www.nytimes.com/2019/04/22/business/china-pigs-african-swine-fever.html
3
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BERTIN, J. Semiologie graphique. Paris – Neuchatel: Mouton-Gauthiers-Villars. 1967.
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... The idea of a causal link between farm pigs and the epidemic is circulating [30] [32] from months, at least April 2020, when it was written [26] that in Italy the top 4 regions (out of 20) by number of cases had the same positions in the ranking by pig density per square kilometer. An interesting coincidence to observe. ...
Preprint
Full-text available
This study is essentially devoted to show statistical correlations between the intensity of the famous 2020 pandemic (variously measured) and the numerical presence of pigs (farm pigs and very cautiously wild boars) and secondarily other livestocks and even humans, following previously published results. On the whole bovine and other livestocks show lower correlations than pigs. The statistical correlation between pigs and the pandemic is studied at the levels of the provinces of Lombardia, the regions of Northern Italy, the regions of Ukraine, the countries of Southern Europe, and sketched for other areas. In Lombardia a very high correspondence is found, where farm pigs presence is overwhelming, and air is so little circulating, preserving the geographical correspondence. Pigs are not pets to contact directly: this study is essentially statistic, nevertheless it suggests that some livestocks, and especially pigs, produce aerosol to which the human virus attaches, allowing a long distance inter-human contagion, which makes questionable almost all the commonly used measures to counter the pandemic. The known protective correlations of the pandemic with the latitude and very likely sunlight are considered and integrated in the model. Clues have been found that the pig correlation fades from Spring to Winter 2020, maybe due to greater air circulation, destroying the geographical correspondence between pigs and the pandemic intensity.
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