Facing South

Swine flu genes traced to North Carolina factory farm

CAFO_hogs.jpgWriting about swine flu last week, we observed that massive hog farms like those clustered near the outbreak's epicenter in the Mexican state of Veracruz "can act as a vector for environmental injustice," and pointed to studies done in North Carolina -- the nation's second-biggest producer of hogs after Iowa -- that found such farms put nearby residents at risk of serious health problems and tend to be concentrated in communities with high poverty rates and a high percentage of racial minorities.

As it turns out, there's a more direct connection between the current swine flu outbreak and North Carolina: Scientists working to understand the genetic makeup of the H1N1 virus that causes the disease have linked it to a virus behind a 1998 swine flu outbreak at an industrial hog farm in Sampson County, North Carolina's leading hog producer.

The Raleigh (N.C.) News & Observer reported that a virus related to the current outbreak was first identified a decade ago at a farm in the eastern North Carolina county. The N&O cited Raul Rabadan, a Columbia University scientist who's studying the new virus's genetics:

"This virus was found in pigs here in the United States," Rabadan said in an interview. "They were getting sick in 1998. It became a swine virus."

It spread among pregnant sows in Newton Grove, N.C., causing them to abort their litters. The virus then spread to pigs in Texas, Iowa and Minnesota -- putting epidemiologists on alert about the new viral strain and the potential for a human outbreak.

A May 1999 N&O story titled "Disease detectives untangle mystery of mutant flu virus" (available in the paper's online archives) reported that the 1998 bug -- a pig virus "wrapped in a shell of human proteins"  -- was isolated by a state government veterinary lab. Similar mutations are suspected in earlier flu outbreaks, including the 1918 Spanish flu that killed more than 20 million people worldwide.

According to that story, the virus was discovered in August 1998 at a 2,400-sow breeding farm owned by Newton Grove, N.C.-based Hog Slat Inc., a leading builder of factory-style hog farms. The company is also one of Sampson County's largest employers -- as is Smithfield Foods, the Virginia-based corporation that owns numerous hog farms near the Mexican community where the earliest case of the current swine flu was identified.

The 1998 North Carolina outbreak began with pregnant sows developing high fevers. A state microbiologist who tested nasal samples taken from the animals was surprised to encounter a virus he didn't recognize -- and his alarm grew when he found that some of the sick animals had been immunized for ordinary swine flu, the N&O reported:

He was concerned for good reason.

Pigs are considered by most virologists to be the primary source of deadly influenza pandemics in humans. Unlike epidemics, which are usually isolated within specific areas, pandemics spread quickly and can cover the world within a few months.

Those pandemic influenza viruses aren't believed to originate with the pigs, however. Most flu bugs that have infected humans in the past have been traced back to aquatic birds such as ducks and geese, suspected as the reservoir for almost all strains of human flu.

But because they are so genetically different, it is extremely difficult for viruses to jump directly from birds to people. That's where pigs come in.

Pigs are ideal mixing vessels, because they can pick up viruses from both birds and humans. And since viruses are always mutating, pigs can produce viruses that have a mix of genetic traits from both birds and humans. After that, it is possible for a potentially deadly strain of avian influenza virus to make the relatively short genetic hop from pigs to people.

The H1N1 virus behind the current flu outbreak contains genetic material from birds, humans and pigs, though it's called "swine flu" because it's a type of virus that typically infects hogs.

The state microbiologist investigating the 1998 outbreak sent samples of the virus to Dr. Robert Webster, a leading virologist at St. Jude's Children's Research Hospital in Memphis, Tenn. Webster identified them as a mix of human and swine virus and concluded the virus had originated in humans before jumping to pigs.

North Carolina public health officials tested workers at the Hog Slat farm who had come in contact with the infected pigs. Those tests showed that 10% of the workers had developed antibodies to the virus, meaning they had been infected although they apparently hadn't become ill.

At the time, health experts said they did not believe the new virus posed a threat to humans -- but admitted the potential was there for future problems:

"We don't know how often these reassortments occur in nature -- probably more than we want to realize," said Dr. Newton MacCormack, chief of the communicable disease control section of the state Department of Health and Human Services.

"We're pretty lucky in that most of these viruses reach a genetic dead end," he said. "The big problem is the rare occasion when one of these viruses gets into a human and begins to be passed from person to person."

That's what's happening in the latest outbreak.

But fortunately, it appears we may get lucky again, as the World Health Organization has said community-level transmissions appear to be occurring only in the United States, Mexico and Canada, according to the Washington Post. And the U.S. Centers for Disease Control and Prevention reported yesterday that the outbreak appears to be milder than initially feared.

The fact that the virus is turning out to be not as bad as it could have been have led some to decry what they consider "hysteria" over the current outbreak. They include U.S. Rep. Ron Paul (R-Texas), who recently called the reaction to the flu "overblown." However, President Obama said the response was justified by the risk presented by a new virus for which people lack natural immunity.

While we agree that overreacting to swine flu is not helpful, neither should this be a moment for complacency -- not given the very real problems the outbreak illuminates. There's a issue here just as critical as whether governments should discourage people from visiting crowded places during a flu outbreak, and that's how governments should best regulate factory farms.

Crowding thousands of pigs into cramped, filthy quarters creates ideal conditions for the fast spread of potentially dangerous viruses. The Humane Society of the United States points out that the unnatural density of such operations enables the large viral loads considered necessary for the emergence of rare flu mutations that can then spread rapidly among animals. The crowded conditions also stress the animals' immune systems, while the enormous quantities of decaying fecal waste predisposes them to respiratory infections and the lack of sunlight allows viruses to thrive. In addition, the industry's heavy reliance on pharmaceutical drugs and vaccines immunologically pressures the virus to mutate. And the flies and other pests attracted to such operations may be able to pick up viruses and carry them for miles.

A report released last year by the Pew Commission on Industrial Farm Animal Production warned of the risks of inadequate U.S. regulation of such operations. It noted that workers at industrial animal farms can serve as a "bridging population," transmitting animal-borne diseases to a wider community. It also pointed to problems with disposing of animal waste, which industrial hog farms typically collect in enormous open-pit lagoons and spray on farm fields, putting nearby waters at risk of contamination with pollutants including viruses.

And lagoons sometimes fail catastrophically, spreading contamination over large areas. For example, a spill from Sampson County's Bearskin Farms in 1995 resulted in the release of about a million gallons of hog waste into a tributary of the Cape Fear River. And that wasn't even the state's worst hog waste spill, a distinction held by Oceanview Farms in coastal Onslow County, where a 1995 lagoon failure contaminated the New River with 22 million gallons of hog waste -- twice the amount of pollution spilled from the Exxon Valdez. The Oceanview disaster killed 15 million fish and closed almost 365,000 acres of coastal wetlands to shellfishing.

In 2007, after years of work by environmental advocates, North Carolina became the first state in the country to ban the construction or expansion of lagoons and sprayfields on hog farms under the Swine Farm Environmental Performance Standards Act. But that law doesn't require the closure of existing lagoons, which remain a very real environmental health threat to numerous rural communities. And of course, the law does nothing to address problems at hog farms in Mexico.

The Pew report offered a number of recommendations to reduce the factory farms' threat to the public, including improved disease monitoring and tracking, improved regulation, and phasing out of intensive confinement. Bob Martin, who directed the Pew study, told the N&O that the latest outbreak shows action is needed, given the very real potential for dangerous viral mixing at industrial hog farms:

"It's a matter of when, not if," Martin said. "The structure of the system is the problem."

If nothing else, the latest swine flu outbreak should spur governments to begin building a safer, more sustainable agricultural structure. And they must reach across national lines to do so, since neither agribusiness nor viruses are held back by borders.

(Photo of factory hog farm from U.S. Geological Survey)


People Referenced:


re: Swine flu genes traced to North Carolina factory farm

Thanks, Sue, for a superbly written and enlightening article.

re: Swine flu genes traced to North Carolina factory farm

the article that i just read is very alarming and laws should be made to protect us from the greed of these people and their ability to destroy our enviroment. please continue with your efforts to shut these farms down. a concerned citizen of duplin county.i will support your efforts!

re: Swine flu genes traced to North Carolina factory farm

yow....that's a sobering thought for all of us, but especially for our kids and grandchildren.

re: Swine flu genes traced to North Carolina factory farm

Seems to me that this is the best argument yet for encouraging the return of family farms while gradually cutting production of factory farming.

re: Swine flu genes traced to North Carolina factory farm

Nice work. I will integrate it into a course I teach in the fall and it's already in the "health impacts" file for a book I've been thinking about writing on the industrialization of pork production in NC for quite a while. Bob

re: Swine flu genes traced to North Carolina factory farm

Vegetarian advocacy groups as well as environmental and animal protection groups have been warning for decades about the inevitable consequences of factory farming. Both the suffering of the animals and of humans could have been averted had these groups been heeded.

It seems to me rather evident that one part of this swine virus problem is America's addiction to the meat centered diet. The most immediate corrective action anybody can take is to simply stop supporting the meat industry, i.e, vote with your dollar. If enough persons face the horrors of the meat industry and react appropriately, these negligent corporations would simply die from attrition. I say let's turn our attention to healthy diet, which is not meat centered, but rather centered on grains, vegetables, and fruits. The countries in the world who follow a diet more like this have far lower incidences of all the killer diseases which we do in the USA. Overeating and eating too high on the food chain just can't be supported by nature. There are simple laws of nature at work here, as the many commenters and the writer of the original article have indicated. I agree. But we need both personal and governmental action to address this wrong direction in our society.

re: Swine flu genes traced to North Carolina factory farm

It must be mentioned that confined animal feeding operations (CAFOs)are not only hazardous to human and ecological health, but are inexcusably cruel and inhumane to the animals that thence suffer the terror and pain of slaughter houses before they end up on our dinner tables. Unless you're buying and consuming the meat, milk and eggs from field-raised animals, you're an accomplice to this for-profit, systematic torture. Factory farming must be banned.

re: Swine flu genes traced to North Carolina factory farm

The U.S. consumes so much meat that there is such a high demand for it here. WE consume more meat in the U.S. then most Countries. It is sad that our need for food is causing cruelty and inhuman treatment of these animals and also endangers our health.

re: Swine flu genes traced to North Carolina factory farm

You need to put a time and date in your byline. Makes things much simpler.

Good story.

re: Swine flu genes traced to North Carolina factory farm

Hey, ya'll? Vegetarians, right?

re: Swine flu genes traced to North Carolina factory farm

Seems to me that the next logical step now is to close our border with North Carolina.

re: Swine flu genes traced to North Carolina factory farm

Seems to me that the next logical step now is to close our border with North Carolina.

Perfect. Move the the militia out of Arizona and set them up there.

re: Swine flu genes traced to North Carolina factory farm

I stopped eating factory farmed meat after watching the documentary "King Corn" and reading the Rolling Stone article "Boss Hog".

I now only buy grass fed and free range meats. They cost more, but I eat less meat and feel much I am healthier. I cannot stand the thought of eating meat produced in this cruel way, or abuse my body by ingesting steroids-hormones-antibiotic and sodium injected meat products.

Americans need to wake up to the fact that Corporations are only interested in profit. They will do anything they can get away with to increase the bottom line, and this includes poisoning the American people with meat contaminated with drugs.

The EU and Japan both refuse to import American meat for this very reason. Change your meat eating habits and support ethical producers.

re: Swine flu genes traced to North Carolina factory farm

and we were so willing to believe it can from mexico

re: Swine flu genes traced to North Carolina factory farm

ahhhhhh im so scared!!!!!!! i live in sampson county and i can see diasese in the air!!!! some one help me!!!

re: Swine flu genes traced to North Carolina factory farm

Hello all --

Just to set some things straight, the North Carolina 1998 influenza (H3N2) was not the predecessor to the current H1N1. Several facts support this: First, the NC 1998 H3N2 was a double mix (genes from viruses infecting humans and pigs), and the current H1N1 is a triple mix (genes from viruses infecting birds, humans, and pigs). Second, the NC 1998 H3N2 virus went extinct sometime in 1999-2000, which is common among influenzas. Third, also in 1998 an H3N2 triple assortant (i.e., bird, human, and pig-sourced genes) was identified out of Texas (and examination of serum banks suggest it had been around at least as early as 1996). Dr. Webster's lab (mentioned in the article) noted that for a decade that virus was highly stable and is still present. So, the NC H3N2 differed quite a bit from the new H1N1, it went extinct nearly a decade before the new H1N1 emerged, and there are other candidates (that we know of).

Unfortunately, one media source got the initial differences between the viruses wrong, and that error has been picked up and repeated (as with the Raleigh N&O article), causing the confusion.

Dr. Rabadan, quoted in the story, is a computational bioscientist (a mathematician) -- he takes massive amounts of genetic data from multiple sources and analyzes it for associations and correlations. He does not do the actual wet-lab work of virus characterization, so he cannot be blamed for getting the names wrong. Whether it came from a TX virus or an NC virus does not really make much difference to his modeling work.

Furthermore, while any time you have large populations concentrated together (whether a hog farm or a big city), you raise the potential for some diseases to flourish. However, you also improve the capability of monitoring and control. The Vera Cruz pig farm in Mexico is actually 40+ miles from the home of the child often identified (incorrectly as it turns out [see below]) as the 'first case' in Mexico, and has tested clear of the H1N1 by the company and by government inspectors. So to claim the farm is the source, flies in the face of reality. Lastly, the overall negative characterization of the farm is disputed by the fact that the farm management's work to improve conditions for its surrounding towns has earned the Mexican Center for Philanthropy’s prestigious social responsibility award (Empresa Socialmente Responsible), for three consecutive years.

Are there farms with environmental issues, animal welfare concerns, and the like? Of course there are. I doubt we can identify any sector, organization, or industry that doesn't have bad apples. But just as it is irresponsible to paint all members of any group with a gross stereotype, the same caveat holds here. The Pew study mentioned in the report is an example of such irresponsibility. I was asked to take part in the study group for the report, but quickly realized the leadership had already decided what the findings would be. So, I declined the invitation. In the end, the scientists who did take part in the Pew study groups have tried to have their names removed from it, since the report did not reflect the actual science.

But back to H1N1. So, if this new H1N1 didn't arise in Mexican pigs, where and when did it originate? We may never know. The CDC has reported that, given the genetic dissimilarities in the subtypes of the H1N1 found in Mexico and USA, it likely started circulating in the people of Mexico sometime in fall 2008, but was only detected in March 2009. Genetic analyses of all eight gene sequences published this month in Science magazine (www.sciencemag.org/cgi/content/full/1176225/DC1) shows a number of near-neighbor viruses actually being Chinese/Asian origin H1N2 influenza. The majority of influenzas originate in southeast Asia for a number of environmental, cultural, husbandry, and marketing reasons -- it would not be a surprise if the new H1N1 had its ancestry trace back to that region. But, again, we may never know.

It all points to the importance of human health, animal health, and environmental health workers needing to come together. You cannot protect one without protecting the others. Over 2/3's of new human diseases have their sources or reservoirs in animals, either domestic animals or wildlife. Environmental changes impact the health of all animals, human and otherwise. Human behaviors, animal population shifts, larger climate alterations, all feedback on each other. This creates a very complicated picture for any population health issue, and new diseases (including influenzas) should always catch our attention. However, we need to be as scrupulous as we can in the facts, because incorrect information leads to inappropriate reactions and plans for animal and public health. Those errors waste time and money, and can do more harm than good.

re: Swine flu genes traced to North Carolina factory farm

Well Said Slenning. If only critical thinking were as viral as influenza.

re: Swine flu genes traced to North Carolina factory farm

Read this article if you want to understand the facts of flu.


CAFU (confined animal feeding units) has little impact. Why do you think the CDC has been in China for years trying to identify the World's next emerging pandemic flu? It’s because people live in the top of a barn with ducks, chickens, and pigs living below them. It’s the perfect petri dish. Move pigs out of CAFO and put them back on the ground for exposure to tricomoniasis, avian domestic and wild foul, weather hardship, etc. and we're back to where China was ten years ago. Today China is smarter; they have to feed their people. Please tell me how many CAFU existed in 1918? Zero. Yet that is the year of the killer flu. The author above is doing nothing but spreading inaccurate information for the purpose of pushing a social agenda. PETA is proud of her. If we have a bunch of wannabe hippies, growing organic food, with a Charlotte's Web menagerie of animals, trying to produce food for 360 million people in 2020, we'll all be hungry, and as Templeton said well, "The rat rules."

re: Swine flu genes traced to North Carolina factory farm

If half the information in this article was true the National Guard would be at my farm this morning to shut it down. I have 8000 pigs on my farm. I have worked inside those houses most every day for the past 16 years and have suffered no side effects. None of my neighbors have notified me of any health problems. Come visit my farm. I will show you that this propaganda is just as I say. This is pure "well meant" disinformation. Thanks for allowing a Pig Farmer to comment.

re: Swine flu genes traced to North Carolina factory farm

"But just as it is irresponsible to paint all members of any group with a gross stereotype, the same caveat holds here."

You know I desperately try to wrap my brain around why this is said over and over again about remotely every factory farm based issue.

What "members" in association with this corruption are so irresponsibly accused? the ill educated consumer? the poor farmer? the corporate ladder?

The thing is its not irresponsible! if anything it is just the opposite. It forces the truth to eventually surface from every side possible. I'm a college student desperately fighting for a better future for the children I've yet to conceive learning more and more each day just how pathetic this world of mine really is.

For farms there aren't even any animal welfare laws to break! every condition in the modern factory of a farm consists of nothing but total defiance of any anti-cruelty law that was painstakingly fought to pass.

there are always bad apples? yea sure if you are talking in the most general sence possible, like the fact that some farmers laugh at a pig choking to death and others turn their heads and respond that it had to be done.

these are pigs, considerably smarter then dogs, with a conscience intelligent enough to be compared with that of a 3 year old human toddler. now I'm not suggesting we all go vegan and frolic around placing daisy chains on hogs heads. These aren't pets, they're food, but they are still living breathing animals. I mean if I was confined I'd be mean as hell too but come on, I cant be the only one seeing it this way.

the sick irony is just that... they are being treated as if they were "bad apples". unclean creatures. literally thrown around in buckets and all.

If I've learned anything its that most people who object are simply up the ass of the pork or beef industry. well . . . time to run for congress.

"The greatness of a nation and its moral progress can be judged by the way its animals are treated" ~Mahatma Gandhi

re: Swine flu genes traced to North Carolina factory farm

Critical thinker(supposedly), so you know, there is not definitive evidence that support your theory that the Killer Flu comes from China, where according to you people live on top of barns co-habitating with barn-yard animals. http://en.m.wikipedia.org/wiki/1918_flu_pandemic?wasRedirected=true

it's also interesting to note that in that link above, the Killer Flu was nickname the Spanish Flu just from the simple fact that Spain reported true and uncensored news on the deadly flu therefore people started to believe it originated from there! Wow, so it's in some peoples' best interest to blame someone else for their screw-ups, like Smithfield Foods and their defenders!! Talk about back-fired.

Some scientist suggest that people should call the recent and mutated Swine Flu, North American Flu, but I don't think that would fly because most of us aren't good at taking accountibility!

re: Swine flu genes traced to North Carolina factory farm

Excellent read, I just passed this onto a colleague who was doing a little research on that. And he actually bought me lunch because I found it for him smile So let me rephrase that: Thanks for lunch!

re: Swine flu genes traced to North Carolina factory farm

Mr. Snelling is paid faculty at North Carolina State U (like most state universities largely funded and influenced by animal agriculture) focusing on animal agriculture production. But I'm sure that had nothing to do with his assessment/analysis...

re: Swine flu genes traced to North Carolina factory farm

If really intensive hog farming favors the propagation of the H1N1 virus accross the world then it is wise enough to arrest its production