Factory farms of disease: how industrial chicken production is breeding the next pandemic

Last December saw 101,000 chickens on a huge farm in the region of Astrakhan, southern Russia, begin to die. The state research center found that H5N8, a new strain of deadly avian influenza, was in circulation. Within days, 900,000 birds at Vladimirskaya were slaughtered quickly to stop an epidemic.
The world's second-ever pandemic is Avian Flu. H5N8 is one strain of the virus that has infected thousands of turkey, chicken and duck flocks in nearly 50 countries. It is not expected to stop.

The Astrakhan case was different. Five women and two men, among 150 farm workers, were tested for the disease. The mild form of the disease was found in one woman. This was the first time H5N8 has been shown to leap from birds to humans.

A civet kitten found on a Tonglu wildlife farm, Zhejiang provincial. As Sars virus spreaders, thousands of these animals were killed in China. Photo by John Footy/EPA

Although the World Health Organization (WHO), was alerted, due to the severity of the Covid-19 pandemic no attention was paid to Anna Popova, chief consumer advisor to the Russian Federation. She warned that there was a high probability of human-to-human transmission. It was imperative that immediate work be started on developing a vaccine.

The origins of Covid-19 are the focus of global attention. However, eight or more strains of avian influenza, which can infect and kill people and are potentially more serious than Covid-19 are regularly being reported from factory farms around the globe.

Dr Michael Greger: We are witnessing an unprecedented rise in the spread of new bird flu viruses.

Although there have been no reports of H5N8 human infections, concern turned to China last week. Since 2014, H5N6 avian flu has infected 48 people in China. Although most cases were linked to those who work with farmed birds in the past, there has been an increase in cases in recent weeks. More than half of all infected people have died. This suggests that H5N6 is growing in speed and becoming more dangerous.

WHO and Chinese virologists are concerned enough to ask governments for increased vigilance. A spokesperson for the WHO Pacific-region stated that although the likelihood of human-to–human spread is low, a greater geographical surveillance of the affected areas of China and surrounding areas is essential to better understand the risk and recent spike in spillover to humans.

At Shanghai Zoo, a crane is seen in the water. A crane reflected in water at Shanghai zoo.

Earlier in the month, China's Centre for Disease Control [CDC] discovered several mutations in H5N6 cases. The spread of H5N6 virus poses a grave threat to both the poultry industry as well as human health, according to Gao Fu, CDC director and Shi Weifeng dean of public and health at Shandong First Medical University.

They state that the zoonotic potential AIVs (avian influenza viruses) warrants constant, vigilant monitoring in order to prevent any spillovers that could lead to catastrophic pandemics.

Factory farming and diseases

Although the WHO suspects that Covid-19 may be linked to intensive breeding of animals on south-east Asia's few wildlife farms, it has no evidence. Intensive livestock farming has been implicated in major outbreaks, including Q fever in the Netherlands and highly pathogenic Avian Influenza outbreaks.

The 150bn-a year poultry and livestock industries and governments emphasize how intensive farming is safe and essential for fast-growing populations of protein. However, scientific evidence has shown that stress and crowded conditions can lead to the spread and emergence of many infectious diseases and act as an epidemiological bridge between humans and wildlife.

UN agencies, epidemiologists, and academics recognize the connection between the emergence and intensification of poultry farming and highly pathogenic avian flu viruses.

The UN's Food and Agriculture Organization (FAO), states that Avian influenza viruses are rapidly evolving into a diverse virus pool. A pathogen could become a highly-virulent agent. In monocultures that involve mass rearing genetically identical animals selected for high feed conversion, a new hyper-virulent pathogen can quickly spread within a flock.

Governments and the industry routinely blame wild birds for spreading avian influenza along migratory routes. But evidence is mounting that intensive farming may be a potential source of new, deadly viruses.

Rob Wallace, an American viralologist, believes that the new flu strains are adapting to poultry production and is no longer possible to blame migratory waterfowl. He says that the infiltration of influenza into poultry and industrial livestock has become so widespread that they now serve as reservoirs for disease. They are their source.

Zhangzhou, Fujian province duck farm where 400,000 ducks were slaughtered per week when the H7N9 bird influenza struck China's poultry market. Photograph: AFP/Getty

Wallace believes that there are high chances of new flu strains or variants spreading to humans, given the fact that more than 20 million chickens are being raised and almost 700 million pigs are being farmed simultaneously.

Sam Sheppard, a Bath University biologist, supports him. He says that overuse of antibiotics, overcrowding, and the genetic similarity among animals create ideal conditions for bacteria, viruses, and other pathogens merge, mutate and spread to humans.

Sheppard studies how keeping animals in a confined space can cause genetic changes in common bugs like campylobacter. These bugs are now prevalent in cattle, poultry, and pigs. These bugs first appeared in the 20th Century, which coincided with large increases in farmed cattle. He says that the bugs have become resistant to antibiotics due to overuse of medicine.

It's not just birds and pigs. The risk of infection increases with intensive breeding, such as Mers in camels and coronaviruses at mink farms.

The Centre of Disease Control, Beijing. One UN agency says that avian influenza viruses are becoming a diverse and large-scale virus pool. Photograph: AFP/Getty

The next pandemic

Marius Gilbert, an epidemiologist from the Universit Libre in Bruxelles, Belgium, and others have shown that bird flu can be linked to rapid intensifications of poultry farming. This is making bird flu more dangerous.

Although public health experts have warned for years about the dangers associated with industrial farming, the stakes have risen since Covid, when the full cost of a pandemic have been realised, according to Michael Greger, a historian and medical doctor who wrote the book Bird Flu. A Virus of our Own Hatching.

Greger claims that there were three periods of human disease. The first was when humans began to domesticate animals around 10,000 years ago. Next, in the 18th century, the Industrial Revolution brought about epidemics of heart disease, diabetes, and cancer. Now, it is because of agricultural intensification, which is leading to zoonotic (or animal-borne) diseases like bird flu, Mers and Nipah, and Covid-19.

He says that the evolutionary alteration to the human-animal bond may have been the raising of poultry, cattle, and pigs under crowded, unnatural conditions.

An unprecedented increase in the number of bird flu virus outbreaks is being observed. These viruses have historically been the most dangerous and have the potential for becoming even more severe than Covid.

Gilbert says that dangerous avian influenza is not caused by factory farming. It is also a result of human-caused changes to the environment. Most viruses that circulate in wild birds pose no danger and have only mild side effects. They can occasionally enter the poultry system and cause mild effects. This is usually due to their environment. In farms, we have seen low-pathogen virus infections become pathogenic.

He says that this can create a vicious cycle where the virus spreads to other birds and can then mutate on farms. There is always a risk that viruses can spread to others if people become infected.

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