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The Avian Flu Epidemic: Massive Impact, Uncertain Future

You might have to be an avid reader of medical journals—or a poultry farmer—to notice that the United States is in the midst of a slow-motion disease disaster.

The disease is avian influenza, and though it has not, as yet, affected any people, it is wreaking havoc nonetheless. As of Monday, almost 26 million chickens and turkeys have either died, or been killed to keep the disease from spreading. Three states—Iowa, Minnesota and Wisconsin—have declared states of emergency. Layoffs have begun at poultry farms, and the industry is warning that there may not be enough surviving turkeys to  fill tables at Thanksgiving. The federal government has released $330 million in emergency funds, and in Minnesota, the National Guard has been called out.

Twenty-six million sounds like a lot of birds—but while the epidemic is devastating to states and to individual farmers, so far it has barely dented the United States’ poultry supply. The U.S., after all, produces about 9 billion meat chickens, 360 million laying hens and 240 million turkeys per year; the current losses equal less than three-tenths of one percent of the total.

Poultry raising, though, is an intricate economy of many moving parts. The potential losses from this epidemic include not only individual farm businesses—that is, the income of farm families, and of their workers and their families—but also the businesses they use, from feed dealers to equipment sales and service to slaughterhouse and packing workers to the cafe in the local town.

Beyond that, there is an international ripple effect as well. Each of the top 10 importers of U.S. poultry products has either banned their being imported or restricted them in some way. Those restrictions extend beyond meat and eggs to breeding stock—which means that, if the epidemic continues, other countries will see cuts in their poultry supply too.

And even more than the economic impact, there is concern about a possible medical one. A particular strain of avian influenza—technically, high-pathogenic H5N1—caused great alarm in 1997. (See my last post on bird flu for a short primer on terminology.) It jumped from birds to humans in Hong Kong, sickening 18 people and killing six of them. It was suppressed only by killing all the chickens in the Hong Kong territory—but flared up again in 2003 in Vietnam, and began moving through Asia and west. To date, according to the World Health Organization, it has sickened 826 people and killed 440, more than half of them.

And because the greatest flu pandemic known to history, the “Spanish flu” of 1918—which killed at least 50 million and possibly 100 million people around the world— began as an avian virus, disease authorities watch any bloom of bird flu carefully, braced in case another strain makes that bird-to-human leap.

There is no evidence yet that this bird flu has. “While we are cautiously optimistic that there will not be human cases, we must be prepared for that possibility and we are taking routine preparedness steps, including studying these viruses further and creating candidate vaccine viruses which could be used to make a vaccine for people if one were needed,” Dr. Alicia Fry of the Centers for Disease Control and Prevention said on a CDC-USDA conference call two weeks ago. “So far, genetic analysis has not shown any of the markers that are known to be associated with increased severity of illness in people or an increased ability to be spread to people or spread among people.”

A remarkable thing about this epidemic: It has been spreading since last December (as I covered at our sister blog The Plate).It was spotted first in British Columbia, hopped cross-border to Washington and Oregon, and then began to move inward across the continent. It exploded when it reached Minnesota, the center of the turkey industry, and Iowa, one of the centers of the egg industry, because the farms where the virus has landed are enormous: One chicken facility held 5.7 million birds, two others held more than 3 million, and the two largest turkey farms housed more than 300,000 each.

I spoke to several scientists working on the outbreak who asked not to be identified. They acknowledged that exactly how this flu is spreading is not clear. The usual source of avian flu is wild waterfowl, primarily ducks, which pick the strains up in Asia without being made sick by them, and spread them across the globe as they migrate. Ducks can intermingle with backyard poultry—and they were observed doing that in the British Columbia outbreaks, which occurred on small farms—but they have little chance of making contact with conventionally raised birds. Those large farms (such as the multi-million-bird ones in this outbreak) keep their birds entirely inside buildings, and are expected to have tight biosecurity precisely because confined conditions make it easier for diseases to spread.

The scientists I spoke to said it is possible the flu is now being spread, not by other birds, but by humans—and not because the humans are infected, but because they are unknowingly transporting the virus from one place to another. That could happen via anything that comes onto a farm and has already been on another farm: a truck, car tires, even the clothing or equipment of delivery drivers, equipment-service workers or veterinary technicians. It could even come from water sources elsewhere on a farm that have been contaminated by ducks landing on them, if the water is used to spray down barns or flush away manure.

If that speculation is correct, then controlling the spread of the virus will be unusually challenging—but it will have to be managed, because biosecurity is the industry’s current best defense. Unlike some other countries, the United States does not routinely vaccinate poultry against bird flu. One researcher I spoke to described an outbreak of this size as being like a 100-year flood: for 99 of those years, the expense of vaccinating flocks would not be justified, and—unless it was mandatory for all producers—could put some farmers at a competitive disadvantage versus other farmers who did not buy the vaccine.

(In fact, the last major outbreak of high-pathogenic bird flu in the U.S. was not 100 years ago, but 32: There was a multi-state outbreak in 1983-84, when 17 million birds died or were killed. Before that, the last large U.S. outbreak was in 1929.)

I asked the sources who talked to me what they expected to happen next, and they were cautious. Influenza viruses prefer cooler weather; in the USDA’s April briefing, officials predicted viral spread would slow as summer arrives. That would solve the problem, but only until autumn, when migrating waterfowl could bring the virus south again. If high-pathogenic bird flu became something that had to be defended against every year, that could force  the poultry industry to change its operations in significant and expensive ways.

What the risk is of that happening, no one yet can say.

17 thoughts on “The Avian Flu Epidemic: Massive Impact, Uncertain Future

  1. good case for going vegan.
    eating animals is simply extremely inefficient, if not entirely cruel.
    As these epidemics show, its also dangerous.

  2. My big worry is that natural mutations could easily produce the highly pathogenic H5N1mutants or even worse, yet unkown deadly mutants against which no ready vaccine is availlable..That could be bad news to human race

  3. You know those “sponsor a child” commercials where a child doesn’t have nutritious food, clean water and baths in a river that is also full of sewage. This is exactly the conditions the food industry is doing to chickens, pigs, cattle, etc. They live tightly packed, standing in their own excrement, eating a diet aimed at getting them to slaughter weight as quickly as possible while foregoing nutritional. No wonder we have rampant Avian Flu, Swine Flu, Mad Cow disease, Ecoli, etc. It’s bread in the same conditions many are fighting to keep our fellow humans out of.

  4. you are all worried about Frickin Thanksgiving? Awwwww……the pilgrims killed the Indians, Now the Turkeys take revenge! Sorry for all the death from cramming Turkeys into death camps, Who’s fault is this ? farmers??? Pigs!!

  5. You know those “sponsor a child” commercials where a child doesn’t have nutritious food, clean water and baths in a river that is also full of sewage. This is exactly the conditions the food industry is doing to chickens, pigs, cattle, etc. They live tightly packed, standing in their own excrement, eating a diet aimed at getting them to slaughter weight as quickly as possible while foregoing nutritional. No wonder we have rampant Avian Flu, Swine Flu, Mad Cow disease, Ecoli, etc. It’s bread in the same conditions many are fighting to keep our fellow humans out of.

  6. I really enjoyed this article, as an Anatomy and Medical Careers student, I find it interesting that this strain of bird flu flares up more in colder weather. As with most viruses, they need and warm, moist environment to be able to incubate and spread. However, this is not the case with this strain. Fantastic article! 🙂

  7. I just presented my essay about the negative effects that factory farming has on humans, animals, and the environment. I feel like I should get extra credit for this article.

  8. Bio-security plays a key role in order to avoid the virus to spread. Further, there is no harm to human kind when it is properly cooked and boiled. Any virus or bacteria will not sustain beyond 70 Degree Celsius Temperatures. Chicken and Eggs are safe. However, it should be cooked properly.

  9. To Kathie,
    Farmers are to blame?! How stupid can a human being be. If you were on life support they would unplug you, because you’re brain dead!! I hope you don’t vote.

  10. Once again we have a disaster caused by big industry cutting corners to
    fatten the bottom line a little bit more while the government turns a blind eye. There is a solution to this problem which is to vaccinate the chickens. The government should mandate this and it wouldn’t have to spend 300 million and counting to bail out the industry. Sure mandating vaccinations adds a fixed cost to the production, but saves money in the long run by preventing disasters like this one. It is sad when both businesses and the government focus on the bottom line and ignore the big picture.

  11. I’m going to guess that the vector path is:

    Wild fowl flyways over a) large poultry farms in the US, and b) roadways leading to same.

    The wild fowl, as with other birds, poop while flying. The poop from infected birds lands on the relevant properties and roads.

    Vehicles track it into farms. Workers on farms pick it up on their shoes from outdoor surfaces, both as brought-in on truck tires and as landed from the sky.

    Wild speculation: some of the wild bird poop dries and spreads as dust, such as from locations near ventilating intakes or otherwise.

    The virus particles tracked in by foot and (speculatively) blown in on a breeze, infect a few members of a flock, and then the virus spreads through the flock.

    BTW, Maryn, I’ve bee following your blog for years on the other site, but didn’t feel like ID-ing myself or taking the time to build a decent pseudo in order to comment there. The ease of posting here means I’ll be around from time to time in the comments. Public health has been an interest of mine since I came of age when AIDS was GRID and brand-new, and the reward for keeping abreast of the subject was an increased probability of avoiding infection (it worked).

    BTW, yes, vax the poultry. Cut the antibiotics and roll out the vaccines.

    Cheers -G.

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