MRSA: the pig contributes to the community

A pig and a hen are strolling along and they see a sign in a luncheonette window: Ham and Eggs, 99 cents. The hen says, wistfully, "Isn't it great the contribution we are making to the community?" The pig replies, "For you it's a contribution. For me it's total commitment." Now the pig may be having his revenge.

The drug-resistant bug, methicillin resistant Staphylococcus aureus or MRSA, is making headlines now that it has emerged from its old role as a hospital acquired infection to its new, more ominous one as a nasty infectious agent loose in the community, where it can infect infecting healthy people or more commonly the elderly or chronically ill. Many people are colonized with MRSA without effect (on them), while others develop serious infections. Pneumonia caused by MRSA is often fatal. So where is the community form of MRSA hiding out? We don't know, but a recent study from The Netherlands shows that it can emerge from animals, in this case pigs.

In 2003 a new MRSA strain appeared in The Netherlands that couldn't be identified by the usual method (pulsed-field gel electrophoresis). There was no evidence of the strain in 2002 to over 21% of the reported cases by 2006. By inquiring into the residential and occupational histories of cases, it appeared that carriers or the new strain were much more likely to be pig or cattle farmers. The geographic distribution of cases also correlated with pig farming. A survey of pig farms found almost 40% carrying the strain and 80% of the farms with at least some pigs with MRSA. So far the even stronger relationship with cattle farming has not been investigated but it seems plausible that livestock will also be shown to carry the bug.

Previous work has shown that humans and their companion animals frequently share MRSA strains, but in these cases it wasn't known in which direction the Staph was traveling as the shared strains were of human origin. In the Dutch study it is clear the MRSA strain emerged from pigs and probably cows into the human population and now constitutes a large chunk of the human infections. The authors speculate that the original Staph may have normal colonizers of animals that became drug resistant in the setting of widespread use of antibiotics in the livestock industry.

The pig is having his revenge and is now making a different kind of contribution to the community.

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"...but in these cases it wasn't known in which direction the Staph was traveling as the shared strains were of human origin."

I believe this is a case of humans being the vectors tranferring the disease to domestic animals which will transfer disease to wild animals and back to humans.

There is more than enough blame to go around for this...and I have fought for years unsuccessfully to get preventative antibiotics out of animal feeds, with limited success...but the fact is if you want the etiology, you follow the pathogen back to its origin.

In the 1960's you could eat off the floors in hospitals in Canada. Then cost cutting began and the first place to cut was cleaners in hospitals.

So in my opnion there are three reasons for antbiotic resistant and the emergence of many drug resistant bacteria...1) haphazard cleaning in hospitals that are now more like pig styes then pig styes...2) disrespect for disenfectants and their indescriminate, haphazard use in hospitals and now in homes...3) The fact that for decades humans would stop antibiotic prescriptions before they should have....4) there also a fourth, over prescribing antibiotics for ear infections etc. but this has a lesser effect then prematurely stopping antibiotics.

As far as veterinary medicine goes, it should be remembered that antibiotics are very expensive and are treated with great respect by farmers and veterinarians.

As far as growth promotant antibiotics, they are and always were a bad idea but lower cost of production. I believe there are more additives in chicken feeds then any other type of feed...

...but even so I don't like them at all, they could not produce the wide spread antibiotic resistance that we have seen.

Maybe the first step is to properly clean and disenfect hospitals such that instead of being a place to go to get healthy...they are becoming the place to go and get sick.

The profit motive of the Capitalist economic system is wonderful to behold. It's benefits are infinite.
The factory farming of pigs may have a relationship to this problem of MRSA. And the factory farming of birds may have resulted in this:
"A 33-year-old man from South Korea died of pneumonia with bird flu-like symptoms in Vietnam's southern Can Tho city, local media reported Wednesday. The man named Lu Chin-chu, whose wife is from the city's Co Do district, died on Tuesday afternoon, 11 hours after being admitted to the Can Tho General Hospital, said Youth newspaper. Specimens from the patient are being tested for bird flu virus strain H5N1.

His father in South Korea is suffering from pneumonia with bird flu-like symptoms, according to his relatives in the city."
You are reading about a human H5N1 cluster in both Korea and Vietnam, in the same family. And the people that flew on the plane with this individual from Korea, who arrived in Vietnam in time to become sick with a possible H5N1 infection, had better hope they do not become sick. Airplanes, in order to reduce costs, recirculate the air in the plane. I love the profit motive. And so if this individual, possibly sick with bird flu, infects others on the plane; we could have the start of an epidemic of H5N1.
If the virus has now become highly contagious through the airborne vector, it may be time to kiss our butts goodbye.

New strain of superbug at Sick Kids' Hospital (Toronto)
Updated Wed. Nov. 7 2007 11:32 PM ET News Staff

Doctors in Ontario have identified a new antibiotic-resistant strain of bacteria that's led to a case of meningitis in a child.
The bacteria, a new substrain of Streptococcus pneumoniae 19A, has caused dozens of ear infections in Massachusetts and New York State.
Now, CTV News has learned that this new strain 19A has caused a serious infection in a child at the Hospital for Sick Children in Toronto.
The child's illness developed into bacterial meningitis, a potentially fatal infection of the fluid around the spinal cord and brain. The child had been otherwise healthy and had received all the vaccinations recommended for children.
Doctors may soon be asked by the Ministry of Health to watch for recurrent ear infections that don't respond to treatment with antibiotics, because they could be the result of this new strain.

continued at CTV News website:-

Zoonotic pig MRSA is certainly an important story.

Also important: As a country, the Netherlands does a far better job of "search and destroy" for MRSA -- screening patients on admission to hospitals, and isolating MRSA-positive patients -- than most U.S. hospitals. (see

A few U.S. hospitals do a similar job (see this article from Evanston Northwest Healthcare at

Peter Sandman and I wrote about the need to raise outrage about MRSA policies in U.S. health care settings, in "MRSA �superbug� risk communication" at

Unfortunately, as soon as there is a MRSA story in the news, officials seem to go into Overreassurance mode, instead of "let's clean up our hospitals" mode. Raising public outrage might help change that.

I'll just add that ESBL E. coli seems to be emerging as a worrisome pathogen from farms in the UK.

Antibiotics are not the boon they once were.

By gaudeamus (not verified) on 08 Nov 2007 #permalink

I think the real issue here is when something like this crops up, why isn't anyone tracking down the source and the path of the infection and taking care of it.

Secondly, why is it that I know what steps to take when a child isn't responding to antibiotic therapy and these "doctors" don't? That's truly outrageous.

Earlier this week in Sylmar, CA a middle school had one of it's students hospitalized with CA-MRSA. They were totally unprepared to respond. Their response was to spray the kids classroom. WTF? Where's the source of the infection? Have the teacher and the classmates been tested? Did you interview the student about his daily "path" in the school and swab the areas in an attempt to rule out the school as the source? Did you refuse to re-admit the student until the source was identified? Does his brother, dog, or pig have MRSA?

They did none of that. They didn't ask the common sense questions. They didn't do the common sense, inexpensive testing. They invited the local media in to video a guy in a white disposable painter suit spray the desks in the classroom in the most half-assed way possible.

This type of moronic incompetence on the part of the school (or the local health department, or the hospital, et al) is the root of the problem. Too many critical individuals who are too stupid to do the job they're hired for make a small, easily managed problem into a growing nightmare.

David B.

I work in an ungent care clinic. I see at least 5 cases of MRSA a day. It's out there. Pray that it is not mutating a resistance to the two antibiotics it is susitable to. Don't pray, it's not worth your time. We are all fucked. Wash your hands and don't pick your nose.

By john mruzik (not verified) on 09 Nov 2007 #permalink