Bird Flu Coming Home to Roost
The Satya Interview with Michael Greger

Photo courtesy of Michael Greger

The avian flu—the deadly H5N1 virus that has killed millions of birds and at least 74 humans—has been a hot topic for discussion recently. But there has been very little attention drawn to the root causes of such highly pathogenic viruses. Michael Greger, M.D., the director of public health and animal agriculture for the Humane Society of the U.S., lays the blame on the rise of industrial animal production.

Dr. Greger is a general practitioner, founding member of the American College of Lifestyle Medicine, and served as an expert witness in defense of Oprah Winfrey at the infamous “meat defamation” trial. In his upcoming book Bird Flu: A Virus of Our Own Hatching (forthcoming from Lantern Books in 2006), Dr. Greger explores the dangers of factory farming on public health and its role in the emergence of new infectious diseases.

Sangamithra Iyer had a chance to ask Dr. Michael Greger about all the buzz around bird flu.

Can you tell us a little bit about the current avian influenza?
Avian influenza has existed in nature for a million years as an innocuous intestinal water- borne virus of wild ducks. It doesn’t hurt the ducks and the ducks don’t hurt the virus. Human influenza started just a few thousand years ago particularly with the domestication of poultry—wild ducks in China.

Every year there is a global influenza outbreak, but it tends to only kill the elderly, infirm and infants, because they don’t have well developed immune systems. Although in the U.S., the influenza may kill tens of thousands of people every year, every few decades a strain arrives that can kill people in the prime of their lives. The 1918 pandemic killed between 50 and 100 million people around the globe. And now we are looking down the barrel of perhaps an even worse pandemic, with the current bird flu H5N1 virus.

What is the current death toll from this virus?
The human death toll stands at less than 100 people. So while it has ferocity, it still has not mutated into easy human transmissibility via a handshake or a sneeze. But essentially every leading public health authority on the planet, from the World Health Organization to the Centers for Disease Control, view this as inevitable, a pandemic of influenza triggered by bird flu killing millions of people—between two million and a billion people across the globe.

What role do you see factory farming as contributing to the problem?
When you have tens of thousands of chickens overcrowded in filthy football field size sheds, beak-to-beak in their own waste, one should not be surprised that these are veritable breeding grounds for emerging infectious diseases.

One can trace H5N1 to the explosion of intensive poultry production in Southeast Asia and the developing world in general. Over the last few decades, meat and egg consumption has really exploded and led to mass industrial animal agriculture and transport—the perfect environment for breeding a super flu virus like this one.

Once this harmless duck virus gets into a broiler shed, all of a sudden the virus is faced with a problem. It is used to being an intestinal virus, spread through pond water. But now the virus can no longer transmit through the pond, and has to find another way to travel. This virus being RNA-based—as opposed to DNA-based—has a very sloppy replicating mechanism and mutates at a high rate. It stops being an intestinal virus and starts spreading throughout the entire bodies of these land-based fowl, eventually finding the lungs, and continues to mutate until it’s a virus capable of airborne transmission. That means it has to be resistant to dehydration, it has to start killing cells of the respiratory tract to trigger coughing so it can spread from one chicken to another. Once you have an airborne virus in one of these broiler sheds, all of a sudden you have tens of thousands of hosts for this virus to continue to mutate and get better at killing these animals.

Unfortunately for the human race there is an evolutionary quirk in that on a molecular level, the respiratory tract of chickens looks surprisingly like the respiratory tract of humans. As the virus gets better at killing chickens, the virus gets better at killing human beings as well. Once that virus makes that final jump to human-to-human transmission, it will trigger the next global pandemic of disease.

The blame can really be laid at the feet of intensive poultry production. This is truly a virus of our own hatching coming back to roost.

Why do you think this started in Asia rather than the factory farms here in the U.S.?
The reservoir of avian influenza is in domesticated waterfowl. China produces 90 percent of the goose meat and two-thirds of the duck meat in the world, and that is [why] all of the last four pandemics probably originated from southern China. That’s where this fecal soup of virus is.

Particularly now with industrial agriculture, there is an unparalleled re-assortment laboratory—a billion people, billions of domesticated fowl, and the pig population is also such that we have this nexus for influenza viruses to breed and explode out of.

In Asia, have most of the reported cases been linked to small family farms or animal factories?
There has never been a case of an outbreak of highly pathogenic avian influenza (HPAI) on any free-range poultry flock. These high-grade influenza viruses only seem to be created within these intensive poultry production environments. So for example in Minnesota, with the migration south of wild ducks, the free-range turkey populations would be infected with influenza, but it doesn’t produce a problem. These are low-grade viruses, and though it might decrease egg production and growth rates, it doesn’t kill the turkeys. It cannot spread effectively because it is outdoors. Sunlight kills influenza. There is good ventilation. They aren’t living in their waste like they would be when they are crowded indoors.

When you have these monocrop chickens bred for carcass quality and growth rates, and not bred for disease resistance, living in unsanitary conditions, then these low-grade viruses have the ability to mutate to high grade which can then go on to kill mammals—pigs, people, cats.

This new form of industrial agriculture is breeding viruses like H5N1 and once this factory farmed virus gets created, it can then re-infect migratory birds. You do have birds flying this virus potentially across every continent in the world. It didn’t originate in these birds, or backyard flocks.

There have been measures employed in Europe like separating birds and pigs, and bringing poultry indoors, to protect domestic birds from migratory birds. Rather than tackle Concentrated Animal Feeding Operations (CAFOs), it appears the response is targeting “free-range” and small family farms. What are your thoughts and concerns?
Now that the virus is out and is in migratory species, the rationale is that we have this highly pathogenic species, so we should take birds indoors. We are assuming a kind of biosecurity that doesn’t exist around the world. It is very difficult to keep this virus out of these intensive confinement operations. Once the virus gets inside, unlike a free-range or pasture setting, it can mutate at unparalleled rates because it has these hosts crammed in together.

There has been talk of intensifying surveillance, stockpiling anti-virals, and vaccine development in the U.S. But is there any serious discussion about changing how we raise livestock?
At this point, we don’t think it is possible to eradicate H5N1, since it has spread into wild bird populations. Right now the focus is on mediating the impact of the current pandemic.

There has been a real negligence in discussing some of the factors that led to the emergence of this virus in the first place. Hopefully in the aftermath, there will be real serious consideration and political will—kind of like a post-9/11 situation, [where] all of a sudden America sat back and was like wait a second, people don’t like us? There was some serious consideration of the root causes.

There are other things that aren’t being talked about that could potentially mediate the spread: eliminate the transport of gaming cocks, eliminate cock fighting in general, regulate poultry transport, use less inhumane methods of slaughter and eliminate the mailing through the postal service of baby chicks from hatcheries. These things could also have animal welfare implications. But at this point, there is very little serious consideration of stopping the pandemic in its tracks.

Given that those working with poultry are the most vulnerable at first, in the U.S., are any measures being taken to protect poultry workers from avian flu?
Right now, poultry workers are at an increased risk, but the risk so far from poultry to human transmission is very low. The virus still has much to learn in terms of adapting to the human species. Once it does make that jump, it won’t matter if you work in a poultry processing plant or a skyscraper, or you’re a meat-eater or vegan. The disease will spread worldwide.

Can you describe what will happen if you come down with this virus?
The problem is that your immune system kills you. The virus triggers an overreaction of your immune system, which attacks your lungs and basically turns your lungs into bloody rags and you essentially drown in your own bloody secretions.

So it is important that people go to their physician and ask for a prescription of Tamiflu. There are still some limited supplies left in drug stores. They need to keep it at room temperature. Within 24-36 hours of initial flu symptoms you take this drug, and a five-day course should dramatically decrease one’s chances of dying.

Are anti-virals like Tamiflu our only combatant? Will Tamiflu work on a mutated version of the virus?
As long as the virus is not resistant to that drug. There are two classes of anti-virals that work against avian influenza. One is Tamiflu, which is expensive, difficult to manufacture, and there is not enough to go around. Here in the U.S. we don’t even have enough Tamiflu to treat one percent of the population. Whether it works or not, it is not going to have a significant impact.

There was another drug called Amantadine, which is cheap—$10 a pound, whereas Tamiflu is closer to $10 a pill. You could make tons of Amantadine and distribute it throughout the world. There is no way the global South could afford something like Tamiflu. But we lost Amantadine as a treatment, because poultry farmers in China were feeding it to their chickens. They were using this human drug of global importance as a prophylactic to treat healthy uninfected birds on these industrial farms. There was an exposé done by the Washington Post—“Bird Flu Drug Rendered Useless” [6/18/05]. So we lost the best chance we had to treat people on a global scale, because of this practice that they learned from the U.S. poultry industry. We are the ones who designed the whole concept of feeding antibiotics to poultry and other animals crammed in these filthy conditions. This risky practice is leading to antibiotic resistance.

So what do you do if you don’t have Tamiflu?
If you don’t have Tamiflu—like most of the world and 99 percent of the U.S.—essentially we are left with hygiene measures. There are two ways you get the flu, either you inhale it or you touch something that someone with the flu has touched. So how can you prevent yourself from getting it? Once the pandemic hits, you stay out of enclosed places with other people. You stay out of movie theaters, public transportation, and you wash your hands like crazy—use alcohol hand sanitizer gels, which are very effective in killing the virus.

Some people think that since you can’t get the avian flu from eating chicken, that eating meat is not the problem. What is your response?
First of all, that’s not true. There have been a number of cases associated with eating chicken and egg products. And not only raw duck blood pudding, a traditional Vietnamese delicacy, but even cooked poultry products.

Experiments show that birds inhaling the virus generate the virus not only in their internal organs, like their lungs, but also within the muscle fibers themselves. Not only can the virus be on the external shell of the egg, but the virus also infects the ovaries of the chickens so the eggs come prepackaged with the virus inside them. When people use soft boiling cooking techniques, mild poaching, sunny side up, you may not be adequately heating the food to a temperature that would kill this virus. Seventy-six million Americans every year come down with food poisoning, which is caused by a pathogen that is completely destroyed by proper cooking and handling techniques.

There is also cross contamination in the supermarket or in the kitchen. That chicken “juice” is a fecal fluid that is absorbed in the cooling tanks in the processing plant. Once dripped upon a cutting board, utensil, kitchen sink, kitchen floor, it could potentially cross-contaminate something that one doesn’t cook, like a salad.

And vegetarians really are not safe. They are not exempt from that fecal fluid dripping on the conveyor belt at the supermarket. Researchers have swabbed the external packaging of raw chicken packages in the supermarket and found levels of salmonella and E. coli on the outside of packaging. You could put your broccoli down and come down with salmonella.

Even if you have a completely vegan household, and you go out and get your organic fruits and vegetables, what were those organic fruits and vegetables fertilized with? They were fertilized with manure or blood meal and that carries the potential for food-borne illness, or from fecal contamination anywhere along the supply chain. So we all need to wash our fruits and vegetables, under running water, scrub them clean, even if they look fine or they are organic.

Currently under the USDA Organic standards, chicken waste from factory farms can be used as organic fertilizer. Does that pose a risk?
Manure is often composted hoping that it will reach temperatures that will deactivate most pathogens. But unfortunately it is more of an art than a science. There continue to be reports of outbreaks of food-borne illnesses caused by vegetarian foods like bean sprouts and alfalfa sprouts. When you fertilize alfalfa with manure, some of the bacteria get into the folds of the seeds, and then when you put that seed in a warm moist environment to sprout in, it becomes the perfect growing environment for bacteria, and there have been cases of E. coli poisoning. All of this food poisoning can be traced back to industrial animal agriculture, where you have this kind of manure overload, and unfortunately, it is being disposed of onto our dinner plate.

Is there anything else you want to add?
Truly the most important thing for the future is to really question industrial poultry production in general. There have been other industrial practices like strip mining, some petroleum extractive practices, DDT, and clear cutting, that society has ruled too environmentally destructive, or pose [too great a] risk to human health. Even if these practices are more profitable for industry, these industries need to be regulated. I think the same kind of view needs to be taken on industrial animal agriculture. With these emerging infectious diseases, it is too great a threat to human health to continue these kinds of systems of intensive confinement. We really have to move towards more sustainable, organic methods—pasture raised animals if anything. If we are going to continue to raise animals for slaughter it needs to be done in a way that minimizes the risk to animal and human health on a global scale.

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