July 30, 2024

Intensive farming could raise risk of new pandemics

Social, economic and political components of infectious disease transmission need greater attention

Intensive livestock farming could raise the risk of new pandemics, researchers have warned.

Industrialised farming is often thought to reduce the risk of zoonotic diseases (those transmitted from animals to humans) because of better control, biosecurity and separation of livestock.

The international study examines the effect of social and economic factors – which are often overlooked in traditional assessments – in potentially improving risk mitigation strategies for intensive farming practices. It finds that the effects of intensifying agriculture “are at best uncertain and at worst may contribute to (emerging infectious disease) risk”.

The study was led by the University of Exeter, UK, and included University of Wollongong, Tufts University, Royal Agricultural University, Clark University, Cambridge Conservation Initiative and the Institute of Development Studies.

Associate Professor Chris Degeling from UOW’s Australian Centre for Health Engagement Evidence and Values, was a contributing author.

“As we take stock after four years of COVID-19, greater attention needs to paid to the social, economic and political components of infectious disease transmission from animals to humans and pandemic risks,” Associate Professor Degeling said.

“Ever since humans first domesticated and farmed animals, this activity has increased the probability of infectious diseases jumping between humans and other species.  As the current global avian influenza pandemic demonstrates, intensive agricultural systems tend to amplify these risks.”

While such risks are usually assessed in terms of microbiological, ecological and veterinary sciences, the new study highlights the need to consider social, economic and political factors.

Lead author Professor Steve Hinchliffe, from the University of Exeter, said: “Disease is always more than a matter of pathogen transmission, contact and contagion.

“The founding myth in intensive farming is that we separate livestock from wildlife and thereby shut off the risk of diseases passing between them.

“But these farms exist in the real world – so buildings and fences can get damaged, wildlife like rats or wild birds can get in, and workers move around.

“Once social, economic and political factors are taken into account, the pandemic risk posed by intensive farming is concerning.”

The paper highlights the expansion of intensive farming and the resulting environmental degradation as factors which can raise emerging infectious disease risks.

It also says intensification leads to a “mixed landscape” – with a variety of farming practices and types – which creates the “worst of all possible worlds in terms of (emerging infectious disease) risk”.

On biosecurity, the paper says some farm businesses find the costs “debilitating”, while regional variations also have an impact.

For example, European farm buildings can be old and costly to maintain, large US farms tend to be open-air concrete structures with netting (to avoid the need for air conditioning), and in subtropical areas biosecurity is balanced against the need to reduce overheating of animals.

“The result is a far from bio-contained environment,” the authors write.

They also note the close ties between large food companies and national authorities – which suggest “regulatory capture… and the difficulty of decoupling interests”.

UOW is committed to addressing the United Nations Sustainable Development Goals (SDG), which provide a shared blueprint to achieve a better and more sustainable future for everyone. This research addresses SDG 3: Good Health and Wellbeing.

ABOUT THE RESEARCH

“Understanding the roles of economy and society in the relative risks of zoonosis emergence from livestock” by Stephen Hinchliffe, Alex Blanchette, Kin Wing (Ray) Chan, Chris Degeling, Jody Emel, Melissa Leach, Ian Scoones and Michael Winter is published in the Royal Society Open Science.

Funders included the Wellcome Centre for Cultures and Environments of Health and the Wellcome Trust.