Chicken Run
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Clearly, stressful, overcrowded confinement in industrial poultry facilities facilitates immune suppression in birds already bred with weakened immunity, offering viruses like bird flu ample opportunities for spread, amplification, and mutation. Placing inbred birds into these kinds of unsanitary environments without the chance for a breath of fresh air or a ray of sanitizing sunshine seems the perfect storm environment for the evolution of the next superflu strain of pandemic influenza. Why then has there been concern about the opposite: free-range flocks?
Sociography scholar Mike Davis blames the international corporate poultry sector for launching a global offensive to blame small producers,1973 the hundreds of millions of farmers raising a dozen or so birds in their backyards.1974 The commercial poultry industry boasts of “biosecurity,” described as the industry’s “buzzword du jour,”1975 arguing that keeping birds confined indoors year-round protects them from exposure to wild birds and any diseases they might be carrying.1976 The U.S. National Pork Board defends large-scale pig confinement using the same rationale.1977
After the Hong Kong outbreak, Webster wrote that hypothetically, past outbreaks of high-grade viruses “could probably have been prevented if domestic poultry had been raised in ecologically controlled houses that maintained a high standard of security and limited access.”1978 This makes sense, but only in theory. In practice, whether trying to stem the spread of H5N1 or prevent outbreaks of highly pathogenic bird flu in the first place, locking birds in industrial confinement operations may increase the public health risk on a global scale.
The Thai poultry industry has used bird flu as an excuse to further industrialize its production systems. Thai poultry baron billionaire Dhanin Chearavanont, a leader in the “Tysonization” of Southeast Asia, convinced the government that his factory farms were the safest way to raise chickens,1979 effectively forcing thousands of small farmers out of business. The government started yoking peasants under contract to corporate “chicken farming estates”1980 and mandated that only owners of closed farms would receive compensation for restocking flocks culled for disease control.1981 But H5N1 is wiping out birds on “closed” farms, too. One of Chearavanont’s own farms containing more than 100,000 birds became infected,1982 and in general, an underreported 2006 Food and Agriculture Organization of the United Nations research report out of Johns Hopkins University found that industrial-scale chicken and egg operations in Thailand were proportionally four-times more likely to suffer outbreaks than backyard flocks.3197 Likewise, despite millions of free-range chickens in France1983 and Nigeria,1984 the first outbreaks in Europe and Africa, respectively, involved a farm confining more than 11,000 turkeys1985 and a battery-cage egg facility in which 40,000 chickens died.1986 The first outbreak in Britain was at a 160,000 turkey factory owned by the largest turkey producer in Europe3198 with an annual turnover of nearly a billion dollars.3199
Thai neighbors Cambodia and Laos present case studies for comparison. While Thailand so heavily industrialized production that it became the fourth-largest poultry exporter in the world,1987 the majority of poultry production in Cambodia and Laos has remained extensive (rather than intensive) and comprised largely of farmers with small outdoor flocks. In which countries did bird flu spread to the greatest extent? In countries where most birds were intensively confined indoors or in those where most of the chickens were raised outdoors? According to the Food and Agriculture Organization, “Evidence suggests that HPAI [highly pathogenic avian influenza] did not become established in Cambodia to the extent that it did in Vietnam and Thailand,” referring to the two countries on either side of Cambodia. “This may be attributable in large part to the primarily extensive nature of the poultry industry (poultry density in Cambodia is much lower (less than 30%) than in Thailand and Vietnam)….”1988
The USDA reported a similar phenomenon in Laos, the other country sandwiched between Thailand and Vietnam. Of the few outbreaks that did occur in the country, more than 90% broke out in commercial poultry operations, not free-ranging flocks.1989 Compared to 115 cases of human H5N1 infection in Thailand and Vietnam, there have been 6 cases recorded in Cambodia and not a single one in Laos.1990
Past outbreaks of bird flu offer further hindsight. In 2004, while H5N1 was blasting across southeast Asia, a highly pathogenic H7N3 outbreak swept through Canada’s Fraser Valley east of Vancouver.1991 Dozens of poultry workers involved in the gassing and incineration of the 19 million chickens culled developed symptoms of infection.1992 Laboratory-confirmed bird flu infections in two workers1993 prompted the World Health Organization to raise Canada’s “pandemic preparedness level” to the same as those Asian countries affected by H5N1.1994 Canadian agriculture interests in government seemed no better than their Asian counterparts in terms of transparency: The Canadian Food Inspection Agency not only initially denied the existence of human infections to the public but withheld the information from the provincial Centre for Disease Control, an omission the Centre said “could have had severe consequences.”1995 Thankfully, both workers were successfully treated with Tamiflu and all other presumed human cases were resolved without reported complication.1996
The backyard chicken farmers blamed the commercial industry for the outbreak,1997 and the industry blamed the small farmers.1998 An industry spokesperson not only denied that high-density broiler chicken sheds played a role in the outbreak, but challenged the assertion that the sheds were overcrowded at all. “Anything that creates a better environment for our birds,” the spokesperson said, “basically makes our industry stronger.”1999
“Only healthy animals produce” is a common defense used by proponents of factory farming. Profitability does depend on productivity, but productivity is not measured on a per-animal basis. “Productivity,” according to University of California-Davis poultry specialist Joy Mench, “is often measured at the level of the unit (e.g., number of eggs or egg mass per hen-housed), and individual animals may be in a comparatively poor state of welfare even though productivity within the unit may be high.”2000 Some of the worst problems are created by some of the most profitable practices, such as breeding for accelerated growth rates,2001 which leaves many birds crippled, brittle-boned, bloated from heart failure, and scarred with ammonia burns after squatting in their own waste. Industry insiders admit that the “success of the modern poultry industry has also created an environment very favourable to highly contagious agents.”2002
Publicly, the industry denies culpability. Internally, it admits to “the growing realization that viruses previously innocuous to natural host species have in all probability become more virulent by passage through large commercial populations.”2003 An August 2005 article in the trade journal Poultry International offers a concise explanation of the role of large-scale production:
The AI virus lives harmlessly in the ducks popular in Asia to control insect pests and snails in rice paddies. If this duck ‘flu passes to chickens kept nearby, it can mutate into a deadly and highly contagious strain that speeds rapidly with accompanying high mortality. The larger the flocks and the more intensive the production level, the more scope there is for the disease to spread for genetic changes to the virus.2004
This is the same conclusion reached by many in the Canadian scientific community. University of Ottawa’s Earl Brown explained to the Canadian Press: “If you get a [H5 or H7] virus into a high-density poultry operation and give it a period of time, generally a year or so, then you turn that virus into a highly virulent virus. That’s what always happens….”2005 Canada’s National Manager of Disease Control within the Food Inspection Agency seems to agree: “Just passing the virus to 3,000 or 4,000 chickens is enough to change a harmless virus into something more pathogenic.”2006 “It is high-density chicken farming that gives rise to highly-virulent influenza viruses,” Brown concluded. “That’s pretty clear.”2007
These conclusions were based on the best available science. The Canadian outbreak first erupted not in a backyard flock or free-range farm, but on an entirely enclosed, “sophisticated” industrial facility. It then jumped from broiler shed to broiler shed, largely skipping free-range farms.2008 The spread of the virus was traced mainly to the human lateral transmission of infective feces via equipment or some other carrier moved from farm to farm.2009 This may also explain how the virus was first introduced into the industrial broiler houses. Chickens don’t need to come in direct contact with ducks to get infected; they just need contact with the virus, which can be walked into a “biosecure” operation on someone’s clothing.2010
In the end, epidemiological analyses placed commercial flocks in the 2004 Canadian outbreak at 5.6 times more likely to be infected than backyard flocks. Infected backyard flocks were discovered after nearby commercial flocks were infected, suggesting that the virus spread from the industrialized operations to free-range poultry, and not vice versa.2011 Birds kept outdoors are more likely to come in contact with wild waterfowl, but also with sunlight, space, and fresh air. Lower stress levels may help their bodies better resist the initial infection, and, since they don’t live on layers of their own waste cramped into poorly ventilated sheds by the tens of thousands, the virus may not spread effectively enough to mutate into a killer. Instead of blaming backyard flocks, attention should be turned, as a former Vancouver Sun editor put it, to the factory farms, the “profitable vulnerabilities built into our food supply.”2012
The largest outbreak of avian influenza before H5N1 exploded in 2004 was the 2003 outbreak of highly pathogenic H7N7 in the Netherlands that infected more than 1,000 people2013 and killed an investigating veterinarian.2014 In an article titled, “Why Factory Farms and Mass Trade Make for a World Where Disease Travels Far and Fast,” the Consumer Affairs correspondent for the Guardian wrote that the disease “spread like wildfire through the country’s intensive poultry industry,” expanding into Belgium and Germany before being contained2015 with the slaughter of 30 million birds.2016
While some blame the rise in factory farming for this outbreak, others blame the rise in free-range farming.2017 Free-range flocks were not, however, found to be at increased risk during the outbreak.2018 According to a review in World Poultry,
A notable feature of the Dutch epidemic was that large, densely-stocked flocks were worst affected. Some extensively managed [as opposed to intensively managed] flocks were infected by the virus without showing significant illness of either birds or people. This does not mean that everyone should return to high-cost, low-output, production systems…but it does mean that some producers might usefully soften housing and management systems which put excessive strain on birds in terms of stocking density, air quality, group size, population instability and general vitality.
After the article goes on to admit to concern that intensive confinement systems may be critically weakening the birds’ immune systems and putting the entire poultry industry at risk, it ends by declaring that “a chain is only as strong as its weakest link!”2019
Although the Dutch virus did kill one person, most of the symptoms it caused were mild, and hundreds of those infected showed no symptoms at all. However, some who did develop symptoms were able to pass the virus to others in their households. Adapting to chickens seems to have adapted the virus to humans. The Netherlands outbreak showed not only that intensive chicken farms may brew a virus capable of human-to-human transmission, but that such a strain can arise in an advanced industrialized country with modern, high-tech poultry facilities.2020
With intensive confinement operations spreading around the globe, southern China may lose its distinction as the purported pandemic epicenter of the world.2021 In Chile in 20022022 and in Italy and Mexico in the 1990s, the same scenario played out. A low-grade waterfowl virus found itself locked inside a building with thousands of chickens, leading to the “now predictable mutation to a highly pathogenic virus.”2023
In Mexico, a low-grade H5N2 virus causing no more than mild respiratory symptoms in chickens found its way into industrial poultry facilities outside Mexico City and turned deadly,2024 eventually affecting nearly a billion birds throughout the country.2025 The “informative, but frightening”2026 lesson to be learned from the Mexico outbreak is that once a harmless waterfowl virus is introduced into millions of domestic poultry,2027 it can “accumulate multiple mutations and become a highly pathogenic strain that causes high mortality.”2028
The Italian outbreak in 1999–2000 among “intensively reared poultry” caused the deaths of more than 13 million birds in three months and evolved into a virus with 100% morbidity and 100% mortality2029 —meaning that once the virus gets into a flock, every bird gets sick and every bird dies. Over the preceding 20 years, the Italian poultry industry had grown and industrialized dramatically, particularly in the Veneto and Lombardia regions, precisely where the 1999 epidemic broke out.2030
The epidemic wiped out both broiler chicken and egg-laying operations. World Organization for Animal Health veterinary officials in Italy at the time wrote, “To date, HPAI [highly pathogenic avian influenza] has affected virtually all intensively reared avian species regardless of age or housing system.”2031 The virus spread faster in broiler chicken sheds than within battery-cage egg facilities. Caged hens would all eventually succumb to the virus, but it had to spread from cage to neighboring cage, whereas it was able to blast its way throughout the broiler shed in one fell swoop, infecting chickens living directly on their own waste. The investigating scientists suspected then that the behavior of viral spread “was probably related to the amount of infected feces in direct contact with the birds.”2032 This suggests that outdoor flocks may be the least at risk since droppings may quickly dry in the sun and open air, rapidly killing any virus contained within.2033