The ills of factory farming reach beyond the ethical as immunologists grow increasingly concerned about a vaccine-resistant virus

Farmed Chickens Factory farming also encourages, in the long run, drug-resistant bacteria. Farm Sanctuary

One of the dire consequences of factory farming is that it encourages the spread of disease due to the close quarters in which the animals live. That’s why they’re fed antibiotics and other medicines when they aren’t sick. This overuse of antibiotics, while beneficial to the flocks and herds in the short term, leads to stronger and more drug-resistant bacteria in the long term. The effect has been widely reported by popular authors like Michael Pollan and Eric Schlosser. What we haven’t heard much about are how viruses can thrive in this environment.

Ian York, an immunologist at Michigan State University, has this week written a story about chicken infected with Marek’s Disease Virus (MDV). The virus was a relatively minor nuisance before industrial scale farming operations brought large flocks of chickens together. Once the disease took hold, a vaccine was developed, but the virus managed to evolve and become more virulent until the vaccine was ineffective. This cycle has happened repeatedly over the past fifty years.

What is most interesting about MDV is the vaccines to combat it have likely contributed to the virus’s strengthening because none of them rendered the virus sterile. While the vaccines were effective at preventing the disease MDV causes, they were not effective at preventing transmission from bird to bird. The larger point York makes is that this may be just what the virus wants—he theorizes that viruses aren’t interested in evolving toward greater virulence but rather toward improved transmission.

That’s especially bad news in the face of the industry’s current eye toward cloning and genetic homogeny in the name of building a more uniform steak or fillet. Improved transmission among a diverse population is one thing, but among a homogeneous population is certain to lead to ruin.

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7 Comments

Great article; this is only one of many reasons I'm vegetarian.

Yep.....vegetarian/vegan here too - just horrible what we're doing to animals in the name of "food". Health/weight/blood pressure couldn't be better - Bonus! No bad feelings about how animals are made to suffer on my account! Win - Win!
Go Veg!

Let's stop for a minute and quit quoting non-referreed, popular press rhetoric. Science has a place in this world, even for the general public. Don't believe everything you read in popular press, but challenge publishers to reference scientific journal articles that are peer-reviewed for sound science and proper research methods. Kudos to those that choose a vegetarian or vegan lifestyle, but don't toot your own horn too loud. Eating "local" and "organic" still has it's negative impact on the environment. Organic foods require greater amounts of land to produce the same amount of food as traditionally-grown production because the organic production process is less intensive than traditional production. This goes for animals and vegetables/fruits. Likewise, transportation of locally-grown foods produces, on average, more emissions than intensive production since more trips are made with smaller loads of product. Whether you eat meat, go vegan, or grow your own vs. buying from a super store, make your decision based on facts rather than hype. P.S. For every animal you don't eat, I'm going to eat three! And, I'm healthy and hot!! :)

there are other concerns beside antibiotic resistant bacteria; for one, animal agribusiness contributes more to global warming than the entire transportation sector (see UN Food and Agriculture Report). As one who will have to live with the consequences of today's generation's actions, I have a vested interest in keeping this planet alive.....Biology should help me though, seeing as those who eat chicken are more prone to cancer and antibiotic resistant bacteria...

How do you think all those carrots feel about being eaten? At least animals can run away. Even if they are caged they can still move. Things such as carrots are buried alive while we grow them.

Look at the by-line on this article. Vaccine resistant bacteria? Then the article is written about viruses.

SaraJ: Thanks for pointing that out! It's been corrected.



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