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Getting a Clue About the Avian Flu

The problem isn’t industrial agriculture. It’s domestication.
(Photo: ChameleonsEye/Shutterstock)

(Photo: ChameleonsEye/Shutterstock)

An aggressive strain of avian flu—the largest to appear in the United States in over 30 years—has forced Midwestern chicken and turkey producers to cull over 15.1 million birds since early March. Most of these losses have occurred since mid-April. The virus, which doesn’t appear to pose an immediate threat to humans, has spread to 10 states. Iowa and Minnesota have been hit the hardest.

The economic impact of the virus—called H5N2—has been severe. Mexico and China have halted the importation of U.S. birds and eggs. Hormel Food Corps, the nation’s second largest supplier of turkey meat, highlights “significant challenges” as it forecasts lower earnings. Contract growers, who have little recourse under such circumstances, are stuck with mortgaged farms and no income. At a meeting in Minnesota some of these growers broke down in tears. “Are we done?,” Iowa’s Secretary of Agriculture Bill Northey asked about the flu. The answer, it seems, is no. Not even close.

How should consumers interpret this situation? The conventional critique of such epidemics is that they result from industrial over-crowding—cramming too many birds into a tight space. GRAIN, a non-profit organization dedicated to sustainable agriculture, articulated this position during a 2006 H1N2 virus outbreak. The virus, it contended, was “essentially a problem of industrial poultry practices.” The proper response, it implied, was obvious: a transition to non-industrial, pasture-based management. Commenting on the current outbreak, Wayne Pacelle, CEO of the Humane Society of the United States, agreed with this perspective, writing that “the root cause” of the bird flu is “inhumane, overcrowded conditions in the poultry industry.”

Poultry scientists and regulatory agencies routinely observe that outdoor flocks would not only fail to lessen the impact of bird flu, but they could easily exacerbate it.

A direct, causal relationship between avian flu and industrial conditions would be fantastic news. Most notably, it would allow us to begin systematically fighting the disease through a surefire method: providing chickens and turkeys more space to roam. Unfortunately, the etiology of avian flu doesn’t support this connection. The problem of avian flu, it turns out, transcends farm size and stocking density and cuts right to the core of animal domestication per se.

Consider how the flu travels. The virus originates in wild waterfowl and shorebirds—especially ducks and geese—for whom the disease (due to the genetic diversity of undomesticated birds) is rarely deadly and mostly asymptomatic. Because the virus colonizes the digestive tracts of wild birds, it spreads to domestic birds through waste (as well as feathers), which can travel in air or water. There are a couple of ways this transmission happens. One, domestic birds raised outside can come into contact with the waste. Two, the infected waste enters the barn where birds are confined, either due to poor biosecurity measures or possibly through vent fans (those feathers) and water transmission.

It’s certainly true that, once the infection breaches an industrial shed, it will spread more rapidly than it would in an outdoor flock (especially if there was less genetic diversity in that shed). It’s also true that, in the barn, it will have a greater chance of mutating into a more infectious, and even zoonotic, strain, thus threatening chickens and humans. These are just two reasons why it’s hard to defend industrial confinement. But it’s difficult to see how raising commercial birds outside would make much of a difference. Specifically, it’s hard to see how it would stop the vector of transmission from wild to domestic birds. Poultry scientists and regulatory agencies routinely observe that outdoor flocks would not only fail to lessen the impact of bird flu, but they could easily exacerbate it.

"If you have commercial poultry free ranging and they come into contact with these wild water fowl ... invariably at some stage they will contaminate this commercial poultry,” according to Dr. Peter Scott, senior research fellow and avian health expert at the University of Melbourne. In an email exchange, he was emphatic that “raising birds outdoors in numbers increases the risk of avian influenza,” that “it is erroneous to consider that ‘non-industrial’ birds are immune to it,” and that “the dramatic growth of free-range egg layers is increasing the risks and outbreaks of avian influenza.”

Free range. (Photo: Phil King/Flickr)

Free range. (Photo: Phil King/Flickr)

Scott is not alone. When Canada experienced an avian flu scare in 2006, the government of Quebec ordered that outdoor commercial chickens be moved indoors. Dr. Francine Bradley, poultry specialist at the University of California-Davis, told NPR that, in light of an impending avian flu threat, “backyard flocks can be more vulnerable if the people do not keep their birds confined and in covered pens.” A year ago, the European Food Safety Authority, assessing the best response to an avian flu outbreak, “identified free range, backyard flocks and poultry holdings near wetlands as being most at risk.”

If the experts fail to convince, there’s always the farmers themselves. On the website—a site where small farmers share agricultural ideas and techniques—a small flock farmer from Tennessee asked this about H5N2: “In view of the current spread of the bird flu, are those of you with free range flocks making any changes to your set up? Are you planning to confine your flock?”

A chicken farmer from North Texas responded:

The virus is being spread by wild birds. If you can figure out how to keep wild birds away from your chickens, you'll be ok. If you do figure it out, let me know, because I don't know how short of enclosing the property with small mesh bird netting.

Another chicken keeper, from Iowa, wrote:

I am worried about it as I have read they [authorities] have destroyed a large quantity of chickens here in Iowa and even a back yard flock in Wisconsin. Though I am not sure what to really do different, except not tell a whole lot of people we have chickens.

When an avian flu hit Australia in 2014, one of the country’s largest free-range egg farmers told the Sydney Morning Herald: “People who have grown and expanded into free range in the last seven years ... they are now carrying this risk factor that you cannot insure against.”

The specific case history of H5N2 transmission further challenges the thesis that industrial confinement of domesticated birds is the root cause of the avian flu epidemic. The current virus began as an H5N8 virus in Asia. Wild birds following migratory pathways in the Pacific flyway brought the virus to North America, where it mutated and mixed with North American strains of the virus to produce several new bird flu viruses, including H5N2.

The problem with avian flu isn’t how domesticated birds are arranged in space. It’s that they’re arranged in space. 

Since December, the United States Department Agriculture and the U.S. Geological Survey have confirmed three types of bird flu in 57 cases that began with backyard chickens and wild captive birds in California, Idaho, Oregon, and Washington. By March, the H5N2 strain had moved to the Midwest.

If the matter at hand was as simple as rearing birds on pasture, then that would have already happened. It would have happened en masse. But, in light of avian flu, raising birds on pasture does nothing but bring domesticated birds into closer proximity to the wild fowl in whose guts the virus originates and migrates.

The point that the current avian flu outbreak drives home with unforgiving logic—logic that so many advocates of pasture-based animal agriculture refuse to face—is that the problem with avian flu isn’t how domesticated birds are arranged in space. It’s that they’re arranged in space. The real question we should be asking as the H5N2 virus rips through industrial sheds and free-range farms alike, is: Why do we bother to pursue such a dangerous practice in the first place?

The Things We Eat is a regular Pacific Standard column from James McWilliams on food, agriculture, and the American diet.