INDUSTRIAL FARMING PRACTICES AID IN NURTURING PATHOGENS

Industrial farming practices that condense animals into small spaces can create ideal conditions for pathogens, Lindsay Campbell wrote for the US trade journal Modern Farmer. 

COVID-19 is just the latest zoonotic disease to emerge and over the years scientific studies have shown that certain industrial farming practices and converting land for agriculture have created ideal conditions for such diseases to thrive. Zoonotic diseases are infections that spread between animals and people. The Centers for Disease Control and Prevention estimates that more than 60 percent of known infectious diseases in people are zoonotic. Despite the fact that the COVID-19 pandemic has been described by some as a “once-in-100-years event,” research shows these kinds of diseases are becoming less rare, and researchers say clearing forests for agriculture is largely to blame. 

“Disease emergence and future pandemics are directly related to habitat loss, human exploitation of wildlife and species extinction,” says Jennifer Lane, a field veterinarian at UC Davis’ One Health Institute, who is involved in an initiative called USAID PREDICT, which looks to reduce future pandemic risks. While evidence at this point indicates that COVID-19 originated in a bat, zoonotic diseases can jump to livestock animals like cows, pigs and chickens. Depending on the disease, it can be transmitted to humans through direct contact, or indirect contact with the animal or through food or water. Lane says that when farms are built near forests, livestock has an increased opportunity to mix with wildlife, which increases the chances pathogens will jump from one animal to the other. She said there is a need to be focused on efforts to either reduce land conversion or to at least be more strategic about it. A study conducted earlier this year by Stanford University scientists looked at farmers in Uganda who lived near forests and found that the chance of transmitting zoonotic disease between wild primates and humans increased when farms have a larger shared border with forests. 

Intensive farming practices are another risk factor that Lane points to. This term, another way to describe industrial agriculture production and confined animal feeding operations, has also been associated with creating environmental conditions that breed harmful pathogens. In May, Samuel Sheppard, a professor of biology and biochemistry at the University of Bath, released a paper that found jamming a lot of farm animals into close quarters and overusing antibiotics can drive up harmful bacteria that can be transferred from animals to humans. “People underestimate perhaps what an impact livestock farming has,” he says, adding that the more animals you have in a confined space, the higher the chance a pathogen has of spreading and the more opportunity it has to adapt amongst different genetic traits of the animals. Certain pathogens, like salmonella, can also thrive on animals that produce stress hormones, which can be common if animals are placed in confined spaces.