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WiccanLiberal
11-22-2015, 06:06 PM
This article makes a good case for discouraging use of any antibiotics in animal feed. It's one of the primary concerns for infectious disease specialists in the development of drug resistant organisms.
http://phenomena.nationalgeographic.com/2015/11/21/mcr-gene-colistin/

Apocalypse Pig: The Last Antibiotic Begins to Fail (http://phenomena.nationalgeographic.com/2015/11/21/mcr-gene-colistin/)I mentioned on Monday (http://phenomena.nationalgeographic.com/2015/11/16/amr-weeks/) that this past week was intended by the CDC, WHO and other health authorities to be a global awareness week for antibiotic resistance. Alarming news that came out of China at the end of the week certainly created new awareness of resistance, but possibly not what the organizers had in mind.
On Thursday, researchers from several Chinese, British and US universitiesannounced in the journal (http://www.sciencedirect.com/science/article/pii/S1473309915004247) Lancet Infectious Diseases that they have identified a new form of resistance, to the very last-ditch drug colistin—and that it is present in both meat animals and people, probably comes from agricultural use of that drug, can move easily among bacteria, and may already be spreading across borders.
This is very bad news.
To understand why, it’s necessary to know a little bit about colistin. It is an old drug: It was first introduced in 1959. It has been on the shelf, without seeing much use, for most of the years since, because it can be toxic to the kidneys. And precisely because it hasn’t been used much, bacteria have not developed much resistance to it. It remains effective.
That neglect turned out to be very fortunate a few years ago when several different resistance factors—NDM, OXA, KPC—started hopscotching around the globe. All of them made bacteria invulnerable to a group of drugs called carbapenems that had been considered a last line of defense: They were the last drugs that were in common use and were able to take care of complex infections that happen in hospitals, caused by E. coli, Klebsiella, Acinetobacter and similar gut-dwelling organisms. Once those bacteria became resistant to carbapenems (earning them the general name of “carbapenem-resistant Enterobacteriaceae,” or CREs), colistin was all that was left—and colistin use began rising.
(From around that time: Here’s a great story that Jason Gale of Bloomberg wrote about colistin (http://www.bloomberg.com/news/articles/2012-06-10/kidney-damaging-drug-seen-attacking-spread-of-superbugs-health), and one I wrote for Nature about CREs (http://www.nature.com/news/antibiotic-resistance-the-last-resort-1.13426). A long series of posts I wrote for WIRED about the discovery of NDM and the bitter political fights over its apparent origin in India can be found here (http://www.wired.com/tag/ndm-1/). Of note, one of the discoverers of NDM is one of the authors of this new research.)
A thing about colistin, which no one seems to have connected the dots on: Because it is an old drug, it is cheap. And because it is cheap, it is an affordable addition to animal feed for all the uses I’ve talked about before (http://phenomena.nationalgeographic.com/wp-admin/edit.php?tag=antibiotics-in-agriculture): to make animals put on muscle mass faster, and protect them from the conditions of intensive farming.
Which, apparently, is how it is being used in China—but not only in China. From the paper:

China is… one of the world’s highest users of colistin in agriculture. Driven largely by China, the global demand for colistin in agriculture is expected to reach 11,942 tonnes per annum by the end of 2015 (with associated revenues of $229·5 million), rising to 16,500 tonnes by the year 2021, at an average annual growth rate of 4·75%. Of the top ten largest producers of colistin for veterinary use, one is Indian, one is Danish, and eight are Chinese. Asia (including China) makes up 73·1% of colistin production with 28·7% for export including to Europe.
<figure id="attachment_171271" aria-labelledby="figcaption_attachment_171271" class="wp-caption alignright" style="box-sizing: inherit; margin: 0px 0px 10px 20px; float: right; max-width: 100%; color: rgb(25, 25, 25); font-family: 'Chronicle SSm 3r', Georgia, serif; font-size: 18px; line-height: 28px; width: 300px;">http://phenomena.nationalgeographic.com/files/2015/11/2015-11-21-03.20.26-pm-300x253.png (http://phenomena.nationalgeographic.com/files/2015/11/2015-11-21-03.20.26-pm.png)<figcaption id="figcaption_attachment_171271" class="wp-caption-text" style="box-sizing: inherit; font-family: pragmatica-web, Helvetica, Arial, sans-serif; font-size: 14px; line-height: 17px; margin: 0px; padding-top: 10px;">Where sampling for the MCR resistance study took place.
GRAPHIC FROM LIU ET AL, LANCET INFECTIOUS DISEASES; ORIGINAL HERE (http://www.sciencedirect.com/science/article/pii/S1473309915004247).
</figcaption></figure>The findings reported this week originate in an ongoing project in which the Chinese authors were looking for resistance in the E. colithat reside in the guts of food animals. (It’s encouraging that such a project exists.) They say they first perceived a colistin-resistant E. coli in 2013, in a pig from an intensive farm near Shanghai, and then noted increasing colistin resistance over several years. They expanded their research to include, not just samples from animals as they were slaughtered, but sampling of retail meat from supermarkets and street markets, and testing of samples previously taken from patients in two hospitals. The samples were collected between 2011 and 2014.
Here’s what they found. The gene they discovered, which directs colistin resistance and which they dubbed MCR-1, was present:


in 78 (15 percent) of 523 samples of raw pork and chicken meat
in 166 (21 percent) of 804 pigs in slaughterhouses
and in 16 (1 percent) of 1,322 samples from hospital patients with infections.

That last is important: The bacteria possessing this resistance were not, as sometimes happens, merely gut bacteria that had acquired the necessary DNA but were hanging out quietly in the intestines and not causing trouble. They are already causing human infections.
And, of most concern: The MCR-1 gene that creates this resistance is contained on a plasmid, a small piece of DNA that is not part of a bacteria’s chromosome. Plasmids move freely around the bacterial world, hopping from one bacterium to another; in the past, they have transported resistance DNA between bacterial species, facilitating resistance’s rapid movement around the globe. This gene, the authors predict, will be able to do that as well.

The rapid dissemination of previous resistance mechanisms (eg, NDM-1) indicates that, with the advent of transmissible colistin resistance, progression of Enterobacteriaceae from extensive drug resistance to pan-drug resistance is inevitable and will ultimately become global.
“Pan-drug resistance,” to be clear, means that nothing at all will work—that infections are untreatable by any known compound.
<figure id="attachment_171274" aria-labelledby="figcaption_attachment_171274" class="wp-caption alignleft" style="box-sizing: inherit; margin: 0px 20px 10px 0px; float: left; max-width: 100%; color: rgb(25, 25, 25); font-family: 'Chronicle SSm 3r', Georgia, serif; font-size: 18px; line-height: 28px; width: 300px;">http://phenomena.nationalgeographic.com/files/2015/11/1000px-Conjugation.svg_-300x272.png (http://phenomena.nationalgeographic.com/files/2015/11/1000px-Conjugation.svg_.png)<figcaption id="figcaption_attachment_171274" class="wp-caption-text" style="box-sizing: inherit; font-family: pragmatica-web, Helvetica, Arial, sans-serif; font-size: 14px; line-height: 17px; margin: 0px; padding-top: 10px;">How plasmids (the blue loops) move among bacteria.
GRAPHIC VIA WIKIMEDIA COMMONS (https://commons.wikimedia.org/wiki/File:Conjugation.svg).
</figcaption></figure>It’s worth noting that not every dire superbug prediction comes true. In the early 2000s, physicians were very alarmed when resistance to vancomycin—like colistin, another last-resort antibiotic preserved from the 1950s—moved via a plasmid fromEnterococcus into Staphylococcus aureus, or staph. At the time, people were already worried about the better-known form of drug-resistant staph, MRSA; the emergence of VRSA, as it became known, ratcheted worries way up. In the end, though, VRSA turned out not to be much of a threat: In 15 years, there have been only 14 (http://www.cdc.gov/hai/pdfs/VRSA-Investigation-Guide-05_12_2015.pdf) such infections in the United States.
But what makes MCR, this new colistin resistance, different from VRSA is the role that agriculture seems to be playing in its evolution and dispersal. There are two problems here. First, that thousands to millions of animals are getting the drug, which exponentially expands the opportunities that favor resistance. And second, that projects such as the Chinese one that allowed the new gene to be discovered are rare—so colistin resistance could begin moving, from animals and into people, without being noticed.
And, in fact, it may be on the move now. The authors note that, while they were writing up their findings, the European Molecular Biology Laboratory received five submissions of bacterial data that appeared to contain the MCR gene—but not from China; from Malaysia.
What will happen next? Unfortunately, we have to wait and see—and hope that systems are built that will perceive this new resistance if it arrives. Meanwhile, I especially appreciate the reaction of Mike the Mad Biologist (http://mikethemadbiologist.com/2015/11/20/last-line-of-antimicrobial-defense-is-falling-colistin-resistance-transmission/), who knows a great deal about resistance in his real life and can be counted on to be exasperated and blunt. He said, about this discovery:

If this doesn’t convince people to get serious about the agricultural side of the problem, I don’t know what will.
__________________________________________________ _____

The message to take away is that the generalized use of antibiotics in agricultural applications is a bad idea. Just avoiding meat raised with antibiotics may be insufficient to protect you. The answer is to limit the use of these drugs to animals that need them and not as a general growth enhancer. The drugs have been found to increase the efficiency of the conversion of feed to growth and therefor bigger profits for the producer. My personal opnion is that the practice may have ended up killing literally millions infected with the fast developing super bugs. Regulatory agencies are only now beginning to have the technological ability to track the DNA in these organisms.

Gunny
11-22-2015, 06:19 PM
This article makes a good case for discouraging use of any antibiotics in animal feed. It's one of the primary concerns for infectious disease specialists in the development of drug resistant organisms.
http://phenomena.nationalgeographic.com/2015/11/21/mcr-gene-colistin/

Apocalypse Pig: The Last Antibiotic Begins to Fail (http://phenomena.nationalgeographic.com/2015/11/21/mcr-gene-colistin/)

I mentioned on Monday (http://phenomena.nationalgeographic.com/2015/11/16/amr-weeks/) that this past week was intended by the CDC, WHO and other health authorities to be a global awareness week for antibiotic resistance. Alarming news that came out of China at the end of the week certainly created new awareness of resistance, but possibly not what the organizers had in mind.
On Thursday, researchers from several Chinese, British and US universitiesannounced in the journal (http://www.sciencedirect.com/science/article/pii/S1473309915004247) Lancet Infectious Diseases that they have identified a new form of resistance, to the very last-ditch drug colistin—and that it is present in both meat animals and people, probably comes from agricultural use of that drug, can move easily among bacteria, and may already be spreading across borders.
This is very bad news.
To understand why, it’s necessary to know a little bit about colistin. It is an old drug: It was first introduced in 1959. It has been on the shelf, without seeing much use, for most of the years since, because it can be toxic to the kidneys. And precisely because it hasn’t been used much, bacteria have not developed much resistance to it. It remains effective.
That neglect turned out to be very fortunate a few years ago when several different resistance factors—NDM, OXA, KPC—started hopscotching around the globe. All of them made bacteria invulnerable to a group of drugs called carbapenems that had been considered a last line of defense: They were the last drugs that were in common use and were able to take care of complex infections that happen in hospitals, caused by E. coli, Klebsiella, Acinetobacter and similar gut-dwelling organisms. Once those bacteria became resistant to carbapenems (earning them the general name of “carbapenem-resistant Enterobacteriaceae,” or CREs), colistin was all that was left—and colistin use began rising.
(From around that time: Here’s a great story that Jason Gale of Bloomberg wrote about colistin (http://www.bloomberg.com/news/articles/2012-06-10/kidney-damaging-drug-seen-attacking-spread-of-superbugs-health), and one I wrote for Nature about CREs (http://www.nature.com/news/antibiotic-resistance-the-last-resort-1.13426). A long series of posts I wrote for WIRED about the discovery of NDM and the bitter political fights over its apparent origin in India can be found here (http://www.wired.com/tag/ndm-1/). Of note, one of the discoverers of NDM is one of the authors of this new research.)
A thing about colistin, which no one seems to have connected the dots on: Because it is an old drug, it is cheap. And because it is cheap, it is an affordable addition to animal feed for all the uses I’ve talked about before (http://phenomena.nationalgeographic.com/wp-admin/edit.php?tag=antibiotics-in-agriculture): to make animals put on muscle mass faster, and protect them from the conditions of intensive farming.
Which, apparently, is how it is being used in China—but not only in China. From the paper:
China is… one of the world’s highest users of colistin in agriculture. Driven largely by China, the global demand for colistin in agriculture is expected to reach 11,942 tonnes per annum by the end of 2015 (with associated revenues of $229·5 million), rising to 16,500 tonnes by the year 2021, at an average annual growth rate of 4·75%. Of the top ten largest producers of colistin for veterinary use, one is Indian, one is Danish, and eight are Chinese. Asia (including China) makes up 73·1% of colistin production with 28·7% for export including to Europe.

<figure id="attachment_171271" aria-labelledby="figcaption_attachment_171271" class="wp-caption alignright" style="box-sizing: inherit; margin: 0px 0px 10px 20px; float: right; max-width: 100%; color: rgb(25, 25, 25); font-family: 'Chronicle SSm 3r', Georgia, serif; font-size: 18px; line-height: 28px; width: 300px;">http://phenomena.nationalgeographic.com/files/2015/11/2015-11-21-03.20.26-pm-300x253.png (http://phenomena.nationalgeographic.com/files/2015/11/2015-11-21-03.20.26-pm.png)<figcaption id="figcaption_attachment_171271" class="wp-caption-text" style="box-sizing: inherit; font-family: pragmatica-web, Helvetica, Arial, sans-serif; font-size: 14px; line-height: 17px; margin: 0px; padding-top: 10px;">Where sampling for the MCR resistance study took place.
GRAPHIC FROM LIU ET AL, LANCET INFECTIOUS DISEASES; ORIGINAL HERE (http://www.sciencedirect.com/science/article/pii/S1473309915004247).
</figcaption></figure>The findings reported this week originate in an ongoing project in which the Chinese authors were looking for resistance in the E. colithat reside in the guts of food animals. (It’s encouraging that such a project exists.) They say they first perceived a colistin-resistant E. coli in 2013, in a pig from an intensive farm near Shanghai, and then noted increasing colistin resistance over several years. They expanded their research to include, not just samples from animals as they were slaughtered, but sampling of retail meat from supermarkets and street markets, and testing of samples previously taken from patients in two hospitals. The samples were collected between 2011 and 2014.
Here’s what they found. The gene they discovered, which directs colistin resistance and which they dubbed MCR-1, was present:


in 78 (15 percent) of 523 samples of raw pork and chicken meat
in 166 (21 percent) of 804 pigs in slaughterhouses
and in 16 (1 percent) of 1,322 samples from hospital patients with infections.

That last is important: The bacteria possessing this resistance were not, as sometimes happens, merely gut bacteria that had acquired the necessary DNA but were hanging out quietly in the intestines and not causing trouble. They are already causing human infections.
And, of most concern: The MCR-1 gene that creates this resistance is contained on a plasmid, a small piece of DNA that is not part of a bacteria’s chromosome. Plasmids move freely around the bacterial world, hopping from one bacterium to another; in the past, they have transported resistance DNA between bacterial species, facilitating resistance’s rapid movement around the globe. This gene, the authors predict, will be able to do that as well.
The rapid dissemination of previous resistance mechanisms (eg, NDM-1) indicates that, with the advent of transmissible colistin resistance, progression of Enterobacteriaceae from extensive drug resistance to pan-drug resistance is inevitable and will ultimately become global.

“Pan-drug resistance,” to be clear, means that nothing at all will work—that infections are untreatable by any known compound.
<figure id="attachment_171274" aria-labelledby="figcaption_attachment_171274" class="wp-caption alignleft" style="box-sizing: inherit; margin: 0px 20px 10px 0px; float: left; max-width: 100%; color: rgb(25, 25, 25); font-family: 'Chronicle SSm 3r', Georgia, serif; font-size: 18px; line-height: 28px; width: 300px;">http://phenomena.nationalgeographic.com/files/2015/11/1000px-Conjugation.svg_-300x272.png (http://phenomena.nationalgeographic.com/files/2015/11/1000px-Conjugation.svg_.png)<figcaption id="figcaption_attachment_171274" class="wp-caption-text" style="box-sizing: inherit; font-family: pragmatica-web, Helvetica, Arial, sans-serif; font-size: 14px; line-height: 17px; margin: 0px; padding-top: 10px;">How plasmids (the blue loops) move among bacteria.
GRAPHIC VIA WIKIMEDIA COMMONS (https://commons.wikimedia.org/wiki/File:Conjugation.svg).
</figcaption></figure>It’s worth noting that not every dire superbug prediction comes true. In the early 2000s, physicians were very alarmed when resistance to vancomycin—like colistin, another last-resort antibiotic preserved from the 1950s—moved via a plasmid fromEnterococcus into Staphylococcus aureus, or staph. At the time, people were already worried about the better-known form of drug-resistant staph, MRSA; the emergence of VRSA, as it became known, ratcheted worries way up. In the end, though, VRSA turned out not to be much of a threat: In 15 years, there have been only 14 (http://www.cdc.gov/hai/pdfs/VRSA-Investigation-Guide-05_12_2015.pdf) such infections in the United States.
But what makes MCR, this new colistin resistance, different from VRSA is the role that agriculture seems to be playing in its evolution and dispersal. There are two problems here. First, that thousands to millions of animals are getting the drug, which exponentially expands the opportunities that favor resistance. And second, that projects such as the Chinese one that allowed the new gene to be discovered are rare—so colistin resistance could begin moving, from animals and into people, without being noticed.
And, in fact, it may be on the move now. The authors note that, while they were writing up their findings, the European Molecular Biology Laboratory received five submissions of bacterial data that appeared to contain the MCR gene—but not from China; from Malaysia.
What will happen next? Unfortunately, we have to wait and see—and hope that systems are built that will perceive this new resistance if it arrives. Meanwhile, I especially appreciate the reaction of Mike the Mad Biologist (http://mikethemadbiologist.com/2015/11/20/last-line-of-antimicrobial-defense-is-falling-colistin-resistance-transmission/), who knows a great deal about resistance in his real life and can be counted on to be exasperated and blunt. He said, about this discovery:
If this doesn’t convince people to get serious about the agricultural side of the problem, I don’t know what will.
__________________________________________________ _____

The message to take away is that the generalized use of antibiotics in agricultural applications is a bad idea. Just avoiding meat raised with antibiotics may be insufficient to protect you. The answer is to limit the use of these drugs to animals that need them and not as a general growth enhancer. The drugs have been found to increase the efficiency of the conversion of feed to growth and therefor bigger profits for the producer. My personal opnion is that the practice may have ended up killing literally millions infected with the fast developing super bugs. Regulatory agencies are only now beginning to have the technological ability to track the DNA in these organisms.



I use garlic and echinacea. I usually don't get anything but sinus infections and it's worked so far. Got tired of sitting around waiting on some chemicals for 4 hours.

Drummond
11-22-2015, 06:45 PM
I enjoy garlic ... it's an inseparable part of my diet. No plate of fish and chips (or steak & kidney pie and chips) would be complete without a garlic clove or 2 to munch through during the meal.

Delicious. I'm sure it all contributes to my general wellbeing. The garlic's great, too.

Garlic and black pudding. Another treat ...

Gunny
11-22-2015, 06:57 PM
I enjoy garlic ... it's an inseparable part of my diet. No plate of fish and chips (or steak & kidney pie and chips) would be complete without a garlic clove or 2 to munch through during the meal.

Delicious. I'm sure it all contributes to my general wellbeing. The garlic's great, too.

Garlic and black pudding. Another treat ...

It also contains the precursor antibiotic to penicillin. I don't eat it. Can't stand the smell. Worked in an Italian restaurant as a teen.

DO I want to even know what "black pudding" is? :laugh:

Noir
11-22-2015, 08:27 PM
//queue of 'I told you so' vegans forms//
The sheer quantities of drugs that have to be feed to animals because of our farming practices is ludicrous, but it gets little attention.

DLT
11-22-2015, 09:53 PM
I enjoy garlic ... it's an inseparable part of my diet. No plate of fish and chips (or steak & kidney pie and chips) would be complete without a garlic clove or 2 to munch through during the meal.

Delicious. I'm sure it all contributes to my general wellbeing. The garlic's great, too.

Garlic and black pudding. Another treat ...

I love garlic (gotta have it in fresh salsa)....but what the heck is black pudding? Do I even want to know? lol

Drummond
11-22-2015, 10:03 PM
DO I want to even know what "black pudding" is? :laugh:

Of course you do ...

Here's a description of it ..


'Black pudding is a blend of onions, pork fat, oatmeal, flavourings - and blood (usually from a pig). As long as animals have been slaughtered to provide food, blood sausages like black pudding have been in existence.

It has a kind of spicy meat flavour to it .. and it's very substantial. You don't have to eat much of it to feel you've eaten a good meal. Depends how it's cooked as to whether there's an indentifiable blood taste to it. If it resembles anything, maybe sausage meat ? But trust me .. anyone liking meat is very likely to like this as well. Highly nutritious, and because of the blood content, is a very high source of iron in the diet (and very readily absorbed, unlike vegetable sources of iron).

Here's what it looks like, after being sliced ...

http://www.debatepolicy.com/attachment.php?attachmentid=7972&stc=1

Jafar would've objected to it, of course ... :D

Drummond
11-22-2015, 10:09 PM
//queue of 'I told you so' vegans forms//
The sheer quantities of drugs that have to be feed to animals because of our farming practices is ludicrous, but it gets little attention.

So do pesticides on vegetables, Noir ..

Drummond
11-22-2015, 10:13 PM
I love garlic (gotta have it in fresh salsa)....but what the heck is black pudding? Do I even want to know? lol

It may SOUND 'iffy', but I insist on saying that, once you've tried it, you're bound to like it. When prepared, it's made in the shape of a sausage, and if it's anything it's a form of sausage, albeit also with a high dried blood content to it.

It has a distinctive flavour, and by my reckoning is delicious. I'd recommend it to anyone.

Especially Jafar ... :rolleyes:

Gunny
11-22-2015, 10:15 PM
Of course you do ...

Here's a description of it ..



It has a kind of spicy meat flavour to it .. and it's very substantial. You don't have to eat much of it to feel you've eaten a good meal. Depends how it's cooked as to whether there's an indentifiable blood taste to it. If it resembles anything, maybe sausage meat ? But trust me .. anyone liking meat is very likely to like this as well. Highly nutritious, and because of the blood content, is a very high source of iron in the diet (and very readily absorbed, unlike vegetable sources of iron).

Here's what it looks like, after being sliced ...

http://www.debatepolicy.com/attachment.php?attachmentid=7972&stc=1

Jafar would've objected to it, of course ... :D

We could just smear it on him. :laugh:

I don't like pork. Got nothing to do with religion and a LOT to do with being Texan. I was raised on beef. If you go in the Deep South here though, they make some good pulled pork BBQ. Best in the Carolinas, GA, AL and TN. You get west and into Texas, you're eating beef.

Drummond
11-22-2015, 10:24 PM
We could just smear it on him. :laugh:

I don't like pork. Got nothing to do with religion and a LOT to do with being Texan. I was raised on beef. If you go in the Deep South here though, they make some good pulled pork BBQ. Best in the Carolinas, GA, AL and TN. You get west and into Texas, you're eating beef.

Beef, pork, I'm happy with either. Give me an inch-thick (or more) beefsteak to chew on, or a couple of pork chops, and I'm a happy man, whichever I eat.

Do they sell kangaroo meat in your part of the world ? I've seen it sold in the form of 'burger meat' in our local Tesco supermarket. [Tried it once .. not bad, though nothing special to it, taste-wise]. I think I also spotted alligator meat once, too, in 'Iceland' (the store, not the country) ...