Scientists argue high-yield livestock farming wrongly blamed for increased risk of pandemics

It is not indoor livestock farming, or the so-called “intensive” farming, that increases the risk of pandemics — quite the contrary. An important study by vets and ecologists has found that outdoor or “free-range” livestock farming can increase the risk of animal-borne pandemics. Instead, the possibility to keep producing animals in indoor facilities with controlled conditions (e.g., temperature, humidity, ventilation) may reduce the risk of pandemics and the emergence of dangerous diseases, including Sars, BSE, bird flu and Covid-19, compared with less-intensive farming.

According to the study’s authors published in the scientific journal Royal Society Open Science, confined livestock farming is less risky because animals are protected and easier to monitor. They have less chance of contact with wild animals and therefore less chance of release of dangerous viruses. Despite reports from the United Nations and other organisations that would like to link “intensive livestock farming” to the spread of zoonoses, the authors argue that “non-intensive” or “low yield farming” require much more soil to produce the same amount of food, and this causes habitat loss. Besides, it displaces diseases-carrying wild animals such as bats and rodents, bringing them closer to farmed animals and humans.

As Harriet Bartlett, the study’s main author, claims: “Intensive or high-yield livestock farming is blamed for pandemics, but those calling for a move away from intensive farming often fail to consider the pandemic risk of farming less intensively and particularly the consequences for land use. Low-yield farms need far more land to produce the same food as high-yield farms. A widespread switch to low-yield farming would destroy and disturb vast areas of natural habitats. This increases the risk of viral spillover, the first transmission from a wild animal, by disturbing wildlife that may well host the next pandemic virus and increasing contact between wildlife, people and livestock”.

Low-yield farms typically involve larger livestock populations, poorer biosecurity, more workers and more areas under farming, resulting in different, but not necessarily lower, disease risks than higher-yielding systems producing the same amount of food”, we read in the report of veterinarians and ecologists at Cambridge and Leeds universities. “A global shift away from intensive farming would require an area of land almost as large as India, inevitably increasing the risk of spillovers. The conversion and fragmentation of natural habitats mean that we are farming in places where livestock and people can come into closer contact with stressed populations of wild animals.”, says Bartlett.

Professor Giuseppe Pulina, President of “Carni Sostenibili” and among the top 1000 animal scientists in the world, explained: “Paradoxically, keeping animals confined gives very high levels of safety. On the contrary, animals in the open air are the most exposed to this disease, especially if they do not have active defences, double fences and constant serological control. On the other hand, animals on the farm have such high safety levels that if the disease were to enter the farm, it would be known immediately. So, the farm would be immediately considered an outbreak, with the quick intervention of the health authorities“.