A New Strain of Drug-Resistant Staph Infection Found in U.S. Pigs

If the newly arrived European strain leads to disease in humans, it would further complicate the struggle against antibiotic-resistant MRSA















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DOES THIS LITTLE PIGGY HAVE MRSA? Image: courtesy Tara Smith

A strain of drug-resistant staph identified in pigs in the Netherlands five years ago, which accounts for nearly one third of all staph in humans there, has been found in the U.S. for the first time, according to a new study.

Seventy percent of 209 pigs and nine of 14 workers on seven linked farms in Iowa and Illinois were found to be carrying the ST398 strain of methicillin-resistant Staphylococcus aureus (MRSA).

The study marks the first time researchers have tested for the strain in the U.S., so there's no way yet to tell when or how it arrived or how widespread it may be, says Tara Smith,  an assistant professor of epidemiology at the University of Iowa in Iowa City and lead author of the study published today in the online Public Library of Science journal, PLoS ONE.

The infection "could be due to movement of animals from farm to farm, or it could be de novo acquisition of [resistance] on this farm," she says. "It is such a small sample that we don’t know whether it has larger significance or not."

The Iowa group undertook the study on two sets of farms, called "production pyramids," while doing surveillance for an unrelated disease. Animals and humans on the second set of farms, also in Iowa, harbored no MRSA. U.S. researchers have been on the lookout for ST398 in the U.S. since it was identified in 2007 in pigs and farm workers in Ontario. The new strain was first found in 2004 in a baby about to undergo heart surgery in the Netherlands, which is nearly MRSA-free because of nationally mandated infection control in its hospitals; it was traced to a pig on her parents' farm.

The strain has spread so rapidly since then that it now accounts for 30 percent of the staph isolates now sent to the Netherlands's national laboratory, compared with 1 percent in 2000, and has started to spread within hospitals. The risk of acquiring ST398 is highest among pig farmers, says Jan Kluytmans, a professor of microbiology and infection control at the Vrije University Amsterdam, who found that 32 percent of patients in one hospital in a pig-farming community were exposed to livestock that carry the bug. "People who live some distance from farms," he says, "have a much lower...rate" of carrying the bacterium.

If it turns out to cause disease in humans in the U.S., ST398 could  further complicate the general struggle against MRSA, which is already being fought on two fronts: against a hospital-acquired strain that began attacking U.S. patients in the late 1960s, and a community strain that began sickening healthy people (who had not been hospitalized) in the 1990s. The staph strains are related, but have different genetic profiles and different resistance patterns. The hospital strain contaminates wounds and causes overwhelming bacterial infections, whereas the community strain causes a range of symptoms from mild infections to rapidly fatal pneumonias. Both can be deadly: In 2007 the U.S. Centers for Disease Control and Prevention (CDC) estimated that in 2005 94,360 Americans contracted invasive infections and 18,650 of them died; 85 percent of the deaths, it said, were caused by the health care strain.



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  1. 1. rich 09:11 AM 1/24/09

    my friends wife died from MRSA 3 years ago. that's bad stuff. i wonder if a vaccine is coming any time soon ?

    http://www.youtube.com/watch?v=nWyQOh64Qy8&feature=channel_page

    goldieshouse.piczo.com

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  2. 2. Cosmic 11:38 AM 1/24/09

    Those of us who live in these farm states amid the nasty antibiotic resistant producing CAFOs need your help. Please ask Ag secretary Vilsak to put a limit on how many hogs can be crammed together on one site. And please join me in a boycott of pork.

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  3. 3. sandyblogs in reply to rich 12:59 PM 1/24/09


    Sorry, Rich. There will never be a vaccine for MRSA. MRSA is a bacterial infection. Vaccines prevent infection from viruses. Two entirely different organisms.

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  4. 4. KJeroH in reply to sandyblogs 02:09 PM 1/24/09

    I guess he means antibiotic. No need to needle on an innocent error.

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  5. 5. Waterman8 02:39 PM 1/24/09

    Why does everyone in the science field want to solve all of the bacterial problems with another DAMMED vaccine ?? Why don't they go back to the basics of the problem and solve it there ?? It starts with the WATER that is being consumed by the animals as well as the crowded conditions. I know of hog farms that changed their WATER with very simple technology and eleminated most of the unhealthy nature, related to hog farming.The bacteria rates were reduced dramaticly, Even the tail biting was reduced and the pigs don't appear as agitated, more calm in their pens. The smell of the whole farm was also reduced. Walter

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  6. 6. Danser 04:14 PM 1/24/09

    I distribute a natural mineral that kills MRSA in humans and animals. It is effective and has zero toxicity. www.nutrasilver.com

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  7. 7. Waterman8 05:49 PM 1/24/09

    I totally believe in the effects of silver products to kill harmful bacteria and know that it, it would be a wise choice in any medicine cabinet. The point I was making is that its the DAMMED polluted WATER, that is DEAD on arrival to those animals. The water used on most farms is ether chlorinated if there using city water . Or it has other toxins from the well that they pump from. Applying the natural physics of a vortex to the WATER used to water the animals greatly reduces harmful bacteria effects to said animals. It's just simple physics in motion !!! Restructured H3 O WATER. I have been working for years with applying this action to water with the VORTEX WATER CHARGER devices that I build and install for people. The results speak for themselves,softer WATER, healthier animals, healthier more abundant plant growth, reduced iron taste and smell,and it kills the chlorine as well. Think that isn't healthy !? Walter waterman008@hotmail.com

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  8. 8. SolShanti 10:31 PM 1/24/09

    you'll never hear it on the news or at a hospital - but you can cure yourself of mrsa with turmeric! - 2-4 tsps 2-4 times per day until two weeks after the symptoms disappear. i got rid of mine this way. you can also kill it on surfaces and clothes with borax - its true. http://www.livetolovetolive.com/loveyourbody.html http://www.naturalnews.com/023159.html

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  9. 9. lizzie123 12:08 AM 1/25/09

    The enclosed Pig Farms are unhealthy AND cruel to the pigs. We should allow animals and birds used for food to roam free like they did 40 years ago, and we wouldn't be having all these problems.

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  10. 10. lizzie123 12:14 AM 1/25/09

    The enclosed pig farms are cruel AND the overcrowded confinement and indiscriminate use of antibiotics is going to continue to wreck havoc on human health as well as animal health. Farmers today have no respect for the animals - they cram as many as they can into containers that do not allow the animals to even more, and they live this way until they die. Then there are the mentally deranged idiots who work in those places who enjoy kicking and beating the animals even as they stand helplessly in cages that do not even allow them to move.

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  11. 11. Mick in reply to Cosmic 10:39 AM 1/25/09

    I have had MSRA twice this year. It can start as a pimple and in a matter of days can it can be a very painful lump the size of a baseball. I contracted it outside of the hospital, from an unknow source. Probably from a surface with the bacteria present.The only treatment is a course of antibiotics and the choice is limited. If you suspect you have it run to your Doctor. It is fast,can be fatal, and contaigous. I am not taking the chance of getting a drug resitant strain from pork. It is to dangerous.

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  12. 12. sds 03:10 PM 1/25/09

    Any kind of monoculture, plant or animal, creates an unbalanced ecosystem. We are causing the very problems we lament, as others have pointed out below. We have to replace our love of money with reverential stewardship of Earth or we're going to wipe ourselves (and everything else) off the planet.

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  13. 13. Narashansa 05:25 AM 2/2/09

    I believe that's why God Almighty has forbidden the flesh of swine (pig) in all his books such is THE LAW, THE GOSPEL, and THE QURAN.

    http://www.miraclesofthequran.com/

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  14. 14. denise in reply to lizzie123 01:30 PM 3/13/09

    I couldn't agree with you more about the cruel and inhumane treatment of factory hogs. It is a disturbing reflection on our society, as a whole, that we allow this abomination to continue. We will pay though,through the pollution of our aquifers, toxic blue green algae in our streams,rivers and lakes, and increasing acidity of our oceans. MRSA is an in your face ( pardon the pun)bell weather of what lies ahead.

    Denise Trafford
    Calgary, Alberta

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  15. 15. denise 02:08 PM 3/13/09

    I totally agree with lizzie about the inhumane and cruel method of producing factory hogs. It says a lot about our society when we allow these abominations to exist. Society prefers to look the other way and avoid the confrontation. Soon we will have no choice, though, when the aquatic life of our streams, lakes, rivers disappear because of toxic blue green algae( phosphorus from hog slurry is it's favorite food) and our aquifers are depleted and poisoned. Let's not forget that the oceans are becoming more acidic, as all this phosphorus is washed into the oceans causing the acidic levels to rise. MRSA is an" in your face" harbinger of what lies ahead for us if we continue down this path.
    Denise

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  16. 16. atphan in reply to Waterman8 01:51 PM 4/17/09

    No one's suggesting utilizing a vaccine as you can't vaccinate for a bacterial infection. The development of new antibiotics combined with improving best practices in farming pigs would ultimately be the best solution for this developing problem. People must understand that while antibiotics are a great health tool, they are not the end all be all for keeping ourselves healthy and safe from scenarios like this.

    http://blog.benchside.com

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  17. 17. staphcureok 07:11 AM 9/6/10

    This is true,Staphylococcus Aureus is resistant to ANTIBIOTICS , my 1 months herbal therapy will cure staphylococcus 100% for sure .I have cured many people with testimonies .
    email - felolakk@yahoo.com
    do contact now .

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  18. 18. staphcureok 07:19 AM 9/6/10

    This is true,Staphylococcus Aureus is resistant to ANTIBIOTICS , my 1 months herbal/natural therapy will cure staphylococcus 100% for sure without any side effects , it is antioxidants ,antibacterial and antitoxins it also has detoxifying and colon cleansing properties..I have cured many people with testimonies .
    email - lewisdavidbb@yahoo.com
    do contact now .

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  19. 19. benny1988 in reply to Waterman8 12:32 PM 5/31/12

    I wouls like more info!

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  20. 20. benny1988 in reply to Cosmic 01:02 PM 5/31/12

    Sorry man this is America!!!

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  21. 21. benny1988 in reply to lizzie123 01:36 PM 5/31/12

    Is that in America?? Not in our barn!!!

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