I am bashfully flattered to report that this blog has inspired, and been quoted in, an episode of the webcomic Lola Lollipop:
Big-eyed kids, talking animals, nutrition, sustainability, and major cute. And, umm, me. Huge thanks to Lola!
I am bashfully flattered to report that this blog has inspired, and been quoted in, an episode of the webcomic Lola Lollipop:
Big-eyed kids, talking animals, nutrition, sustainability, and major cute. And, umm, me. Huge thanks to Lola!
You have to love a scientific commentary that starts this in-your-face:
“Show us the science that use of antibiotics in animal production is causing this antibiotic resistance,” Dave Warner of the National Pork Council told the Washington Post back in June 2010, responding to a Food and Drug Administration (FDA) guidance document advising against the sub-therapeutic use of antibiotics in livestock.
Well, here’s some.
To be clear: That’s the paper’s language, not mine. The gut-punch challenge comes from an editorial that is only on the web so far but is scheduled for publication in the journal Clinical Microbiology and Infection. It accompanies a research article that makes an important claim:
Chickens, chicken meat and humans in the Netherlands are carrying identical, highly drug-resistant E. coli — resistance that is apparently moving from poultry raised with antibiotics, to humans, via food. [Read more…]
So, antibiotics. Given to farm animals. (Yeah, that again.) How does that work, anyway? Pills? Injections? Daily massage with specially compounded creams?
Not quite. Farm animals overwhelmingly get antibiotics in their feed. (You knew that.) And a new paper in the journal Environmental Health Perspectives explains what a bad idea that is: Animals that are given “free choice medicated feeds” (FCMF, in the jargon) can overdose or under-dose themselves, leading not only to the creation of antibiotic-resistant bacteria but to the accumulation of antibiotic residues in their flesh that can persist past slaughter.
There are two issues hidden in this. The first is the practice of giving tiny doses of antibiotics as “growth promoters,” a use that dates back to the late 1940s. Despite a fair amount of study, there are still competing explanations for how this actually works, but the results are clear: Give animals micro-doses of antibiotics, and they put on weight faster, meaning they get to market size and can be sold — and replaced by another batch to whom the same thing happens — more quickly than if the drugs were not being used. The second is using treatment-sized doses in feed to take care of any illnesses among animals, as well as to protect animals who might pick up those illnesses in the close quarters of confinement agriculture.
If you view animal raising as an industrial-style process, the equivalent of making widgets on a production line, then medicated feed appears to make economic sense, because it offers a substantial return for little forward investment of money or labor. But as this paper picks apart, medicated feeds are not the bargain they seem. [Read more…]
Rep. Louise Slaughter (D-NY), Congress’s only microbiologist, said late today that she plans shortly to reintroduce PAMTA, the Preservation of Antibiotics for Medical Treatment Act, a timely move given the collapsing antibiotic market (see this morning’s post) and continuing reports of resistance moving off farms (as in this post).
PAMTA would direct the FDA to re-examine its approvals of veterinary antibiotics that are close analogs of ones used in humans, because they can stimulate the development of resistant organisms. When those organisms move off the farm, as research shows they do, they then cause illnesses that cannot be treated by the functionally identical human drugs.
The Union of Concerned Scientists said in 2008 about an earlier version of the bill:
The FDA is aware of the problem of antibiotic resistance due to overuse in animal agriculture, but the agency’s process for reviewing and withdrawing drugs from the market is far too slow and cumbersome. A recent effort to withdraw an antibiotic from use by poultry producers due to concerns about human antibiotic resistance lasted for more than five years, costing millions of taxpayer dollars. And while the judicial proceedings dragged on, disease-causing bacteria continued to outwit antibiotics.
While some producers and retailers of meat products have announced policies that take steps to curb antibiotic use, private-sector initiatives to reduce antibiotic use in animal agriculture are relatively rare, limited in scope, and difficult to verify. Federal action is needed to achieve comprehensive reductions and create a level playing field for all producers and retailers.
Passage of PAMTA is critical to keep antibiotics working for human health. In addition to averting the harmful effects of antibiotic overuse on human health, curtailing animal use of antibiotics will encourage producers to raise animals in better living conditions that are less conducive to disease.
Parenthetically, it is flattering to see Slaughter reference new data on the amount of antibiotics used in animals in the United States — almost 29 million pounds — and the percentage of the total market antibiotic market that represents: 80 percent. Those pieces of news were broken over the Congressional break by myself, here at SUPERBUG, and by Ralph Loglisci at the blog of the Center for a Livable Future.
Last night, the Journal of the American Medical Association posted ahead of print an editorial by Dr. James Hughes, former director of the National Center for Infectious Diseases at the CDC and now a professor of medicine and global health at Emory University. It’s a blunt and eloquent plea for attention to a problem that many people haven’t yet faced up to: We’re running out of antibiotics.
Antimicrobial agents have saved millions of lives and improved the outcomes for countless patients since these drugs were introduced in the early 1930s. However, the effectiveness of these lifesaving resources is at risk. Many medical advances that physicians and patients take for granted—including cancer treatment, surgery, transplantation, and neonatal care—are endangered by increasing antibiotic resistance and a distressing decline in the antibiotic research and development pipeline. (JAMA Hughes)
Drug resistance is a biologic inevitability — but in the 83-year history of the antibiotic miracle, starting from Fleming’s first recognition of natural penicillin, whenever resistance made one drug useless, another drug came along to save us. Those days are over. [Read more…]
When I talk about farming, I usually focus on antibiotic over-use and the way that it stimulates the emergence of drug-resistant organisms. That’s part of what my recent book is about, and to me, it’s the critical piece in the entire discussion of industrial-scale agriculture. If we didn’t use antibiotics in such vast quantities, confined animal-feeding operations, CAFOS, couldn’t exist: Animals couldn’t survive in those conditions without them.
But so many other negatives come from CAFOs — not just antibiotic resistance, but air and water contamination, and chronic human diseases caused by effluent and pollution. I’m grateful to be reminded of that via a webinar hosted this afternoon by the Institute for Agriculture and Trade Policy, which threw a sharp light on the impact of industrial-scale hog farming in North Carolina.
The webinar took a close look at new research by University of North Carolina associate professor Steven Wing. His paper, just published on the website of the journal Epidemiology, details the acute physical symptoms experienced by North Carolina residents who live in areas near very large hog farms: eye irritation, wheezing, chest tightness, shortness of breath, sore throat and nausea.
Emerging from the farms, Wing said, are “dust, and particles from dried feces, as well as spraying of waste that aerosolizes that material. There are several important gases such as ammonia and hydrogen sulfide… as well as bioaerosols, which include endotoxin from dead bacteria. Some of these materials… are allergenic and can cause respiratory problems.”
(See Wing’s image above of manure spraying, and dead-pig disposal, outside a North Carolina hog farm.)
To get that data, Wing and colleagues at UNC and Mount Sinai School of Medicine collaborated with residents of eastern North Carolina, especially the Concerned Citizens of Tillery, in a project dubbed Community Health Effects of Industrial Hog Operations (CHIEHO). They recruited 101 adults in 16 communities who agreed to sit outside for 10 minutes twice a day, every day for two weeks, and to log their symptoms and also measure their lung function with a flow meter. Separately, the team measured ambient air pollution with continuous monitors that were parked in each community.
Overall, between September 2003 and 2005, they received 2,900 responses about people’s symptoms in the previous 12 hours, 2,600 about symptoms that were provoked by those episodes of sitting outdoors, and 1,900 error-free measurements of lung function. And — no surprise for anyone who knows what these farms look like and smell like — the symptoms tracked with the air pollution measurements.
Wing asked: “Is it fair to tell anyone they can’t go outside their own home because it is too polluted to be there?”
Here’s why conditions outside those eastern North Carolina houses are so bad. Within two miles of each of the communities that contributed to the research, there was an average of 42,000 hogs. Within North Carolina as a whole, there are more than 10 million hogs on more than 2,400 farms. The distribution looks like this:
The spots where the dots cluster most densely are Duplin and Sampson counties. Duplin contains 45 hogs for every resident; Sampson, 32. Something else those areas have in common, mentioned during the webinar by Naeema Muhammad, from Concerned Citizens of Tillery:
Most of those operations are in eastern North Carolina, and eastern North Carolina is where you have your predominantly African-American communities, …other communities of color and also your highest rates of poverty. Looking at that map, we are able to use the phrase “environmental racism.”
Wing and colleagues add in their paper:
…in low-income communities of color… there is more potential for exposure to outdoor air pollutants due to older homes that are not air tight and have no air conditioning. Many residents also lack the financial resources to travel and choose activities that could help them avoid high pollution. Exposure to air pollution from hog operations is an environmental injustice in rural areas hosting facilities that supply pork to populations spared the burdens of its production.
IATP said today they will subsequently post a recording of the webinar along with its slides; I’ll update when it goes live.
Cite: Schinasi, L et al. Air Pollution, Lung Function, and Physical Symptoms in Communities Near Concentrated Swine Feeding Operations. Epidemiology 2011;22: 208–215. DOI: 10.1097/EDE.0b013e3182093c8b
Images: Dead pigs and manure spraying at a North Carolina farm/Institute for Agriculture and Trade Policy + S. Wing, UNC; map of North Carolina hogs farms/IATP + S. Wing, UNC (adapted from Wing et al. 2001)
When we talk about the emergence of antibiotic resistance, two factors usually get the blame: the overuse of antibiotics in human medicine and in agriculture. In both cases, the drugs’ presence exert selective pressure on bacteria, encouraging them to develop or acquire resistance genes that will protect them.
But there’s another way that bacteria are exposed to antibiotics. It’s through wastewater: residues from antibiotic manufacturing, retail drugs dumped because they are expired or no longer needed, and sewage — because a percentage of the drugs we take (and give to animals) pass through our bodies unused, and also pass intact through municipal wastewater treatment when it exists.
I wrote about this a bit last September, just after this blog launched, in the context of how difficult it can be to get rid of prescription drugs that you no longer need or want. (Plea: Don’t flush them.) But a new paper in PLoS One underlines that this problem is much bigger than the bottles cluttering your medicine cabinet.
For several years, faculty from several universities in Sweden have been tracking the content of wastewater flowing into a river near Hyderabad in India, a city that is a center of generic drug manufacturing. (For a sense of how saturated the local environment is with pharma firms — more than 90 — check the map at right.) Previously, they had found levels of fluoroquinolones high enough to kill fish and permeating drinking-water wells in villages. (For humans, the most familiar fluoroquinolone is Cipro.) For this paper, researchers looked specifically at bacteria living in parts of the river where that industrial pharma effluent is flowing, to see whether they were developing resistance in response to that exposure.
Answer: Oh, yeah. Using a method called “multiplexed massively parallel pyrosequencing” (which I love just saying out loud), the team analyzed the bacterial DNA and found it loaded with resistance genes that would confer protection to multiple classes of antibiotics: fluoroquinolones, aminoglycosides and sulfonilamides. At three sites downstream of the key wastewater plant that processes the effluent, known resistance genes accounted for 1.7% of all the DNA they analyzed. Along with those genes, they also found two previously unknown plasmids that contained genes conferring resistance to fluoroquinolones (qnrD) and sulfa drugs (sul2).
It’s important to say that the bacteria in the river that were harboring these resistance genes were not disease-causing bacteria. It’s also important to say that is only minimally relevant. Once resistance factors arise, they move with surprising speed between bacteria and also across bacterial species. In the downstream samples, they also found abundant integrons and transposons that would allow the genes to move, reinforcing the case that resistance was evolving at these spots because of the antibiotic-laden effluent.
This Indian river is a hot spot because of the concentration of manufacturing along it — but it’s not the only offender. Last year, Chinese scientists reported on very high levels of oxytetracycline stimulating bacterial resistance in a river in China. In January, British scientists reported similar results for a river in Cuba. And as I said last fall, the US Geological Survey has found pharmaceutical residues in 80% of the 139 US streams they sampled in 2002.
National and international health agencies, and medical societies and NGOs, have programs that seek to reduce the overuse of antibiotics in human medicine. There’s increasing pressure, as we talk about here all the time, to push back against the overuse of antibiotics in farming. But the thought that antibiotics are spreading freely in groundwater, lakes and rivers is truly disturbing. Curbing that will require a whole different level of effort.
Cite: Kristiansson E, Fick J, Janzon A et al. 2011 Pyrosequencing of Antibiotic-Contaminated River Sediments Reveals High Levels of Resistance and Gene Transfer Elements. PLoS ONE 6(2): e17038. doi:10.1371/journal.pone.0017038
CBC News, the Canadian national TV network, has caused a stir in the food-blog world with the results of a nationwide investigation that found antibiotic-resistant bacteria contaminating supermarket chicken. In its words:
Chicken bought at major supermarkets across Canada is frequently contaminated with superbugs — bacteria that many antibiotics cannot kill — an investigation by CBC TV’s Marketplace has found.
Marketplace researchers — along with their colleagues at Radio-Canada’s food show L’Epicerie — bought 100 samples of chicken from major grocery chains in Vancouver, Toronto and Montreal… The 100 samples were sent to a lab for analysis. Two-thirds of the chicken samples had bacteria. That in itself is not unusual — E. coli, Salmonella and Campylobacter are often present in raw chicken.
What was surprising was that all of the bacteria uncovered during the Marketplace sampling were resistant to at least one antibiotic. Some of the bacteria found were resistant to six, seven or even eight different types of antibiotics.
“This is the most worrisome study I’ve seen of its kind,” said Rick Smith, the head of Environmental Defence, a consumer advocacy group.
I haven’t had time to watch the full program, but no question I think this kind of reporting is worth doing. Nothing brings the threat of agricultural antibiotic use home to people like showing them that resistant bacteria are living on the meat they might have brought home last night.
One important point, though: Don’t think for a moment this is just a Canadian problem.
Last month, a team from the University of Ioannina in Greece analyzed in Foodborne Pathogens and Disease 428 samples of various retail meats they bought in northwest Greece over three years:
E. coli from chicken exhibited high rates of resistance to ciprofloxacin (62.5%) followed by lamb/goat (10.9%), pork (15.7%), and beef (27.9%) meat. Resistance to nitrofurantoin dominated in the lamb/goat isolates (60%). Resistance to tetracycline predominated in pork (68.2%) and chicken (62.5%), and resistance to aminoglycosides dominated in lamb/goat meat isolates. S. aureus resistance to clindamycin predominated in lamb/goat isolates (50%), whereas resistance to ciprofloxacin predominated in the pork strains, but no resistance to methicillin was observed. Of the enterococci isolates 21.1% were resistant to vancomycin. High resistance to ampicillin (96%) was observed in Y. enterocolitica and all of the C. jejuni isolates were resistant to ampicillin, cephalothin, and cefuroxime. These results indicate that meat can be a source of resistant bacteria, which could potentially be spread to the community through the food chain.
Last year, a team from the University of Iceland found fluoroquinolone-resistant E. coli passing from chickens to humans there (the drug Cipro is a fluoroquinolone, and the human isolates were Cipro-resistant), a multi-institution team from Canada found resistance to third-generation cephalosporins in Salmonella enterica spreading from chicken meat to humans, and the Irish quasi-governmental group SafeFood released a long report (and hosted a conference) on “The Problem of Antimicrobial Resistance in the Food Chain.” And of course MRSA ST398, the strain of drug-resistant staph that arose in food animals, has now been found in retails meats across the EU.
Oh, but none of those countries are the United States, you say. Then take a look at these:
Those graphics come from a little-read report put out every year by the US Food and Drug Administration as part of its participation in NARMS, the National Antimicrobial Resistance Monitoring System that’s shared by the FDA, USDA and CDC. The FDA handles the part of NARMS that looks for resistant bacteria in meat (CDC does human illnesses, USDA does live animals), and the figures above show the percentages of Salmonella and enterococci that were found in retail chicken breasts between 2002 and 2008 (the most recent report) and were resistant to various drugs. The bar along the bottom of each figure shows the major drug classes. So in 2008: 45% of Salmonella on chicken were resistant to tetracycline and 30% to penicillins; among enterococci (common gut bacteria, and therefore common contaminants of meat during slaughtering), 65% resistant to tetracycline and more than 90% to lincosamides, which include the everyday drug clindamycin.
In the narrative portion of the report, the FDA said:
38.2% of chicken breast Salmonella isolates were resistant to ≥ 3 antimicrobial classes in 2008 compared to 51% in ground turkey, an increase in both from previous years. From 2002–2007, multidrug resistance to ≥ 3 antimicrobial classes ranged from 20–34.4% among chicken breast and 20.3–42.6% for ground turkey. More than 15% of chicken breast and ground turkey isolates showed resistance to ≥ 4 classes in 2008.
So, just to underline: Multi-drug resistant superbugs aren’t only on chicken in Canada; if you buy chicken in the United States, they are more than likely on your chicken too.
And whatever country they are occurring in, the solution is the same. Drug-resistant bacteria in food won’t diminish until we reduce the amount of drugs that food animals receive while they are raised.
Update: At Grist’s Meat Wagon, Tom Philpott very kindly points out that I actually broke the news of the latest NARMS report, which I didn’t realize (it was a busy day; see my next post for why). Apparently the report was posted to the FDA web site on Dec. 17, but neither of us can find any evidence that it was publicized, such as a press release on the FDA’s press site. His larger point is important:
We find out from the report that the FDA has been monitoring the situation since 2002 — and finding plenty of antibiotic-resistant strains on meat sold directly to consumers. And they’ve been sharing the information with other leading regulatory/public health agencies — but not so much to the people they’re supposed to be protecting and informing: i.e., us. … six weeks since the FDA report and a year since Sharfstein’s testimony [in 2010, promising scrutiny by the Obama adminsitration – m.], policy hasn’t moved at all. Where are the loud public statements from the FDA trumpeting the fact that our factory farms are cooking up superbugs that make their way to our meat? Where’s the USDA on this topic, which is supposed to protect the public from tainted meat? Where’s CDC?
The New England Journal of Medicine last week published the results of a Phase 3 trial of a new antibiotic called fidaxomicin, made by a company called Optimer Pharmacuticals. Fidaxomicin is the first of a new class of antibiotics called macrocycles; it’s a narrow-spectrum drug aimed specifically at Clostridium difficile, the bacterial, toxin-producing, potentially fatal infection of the gut that occurs when broad-spectrum antibiotics have killed off the other populations of bacteria that normally live in the intestines.
Fidaxomicin’s existing competition is vancomycin, the 50-year-old broad-spectrum big gun used for MRSA and many other serious bacterial infections. As compared against vancomycin, fidaxomicin was “noninferior,” in industry jargon; its selling point was a lower rate of recurrence of C. diff among patients who received it compared to those getting the older drug. From the paper:
A total of 629 patients were enrolled, of whom 548 (87.1%) could be evaluated for the per-protocol analysis. The rates of clinical cure with fidaxomicin were noninferior to those with vancomycin in both the modified intention-to-treat analysis (88.2% with fidaxomicin and 85.8% with vancomycin) and the per-protocol analysis (92.1% and 89.8%, respectively). Significantly fewer patients in the fidaxomicin group than in the vancomycin group had a recurrence of the infection, in both the modified intention-to-treat analysis (15.4% vs. 25.3%, P = 0.005) and the per-protocol analysis (13.3% vs. 24.0%, P=0.004). The lower rate of recurrence was seen in patients with non–North American Pulsed Field type 1 strains. The adverse-event profile was similar for the two therapies. (NEJM Louie et al.)
Fidaxomicin has been in the works for a while — it was given Fast Track status by the Food and Drug Administration back in 2003 — and it has faced some criticism for not being different enough from vanco to justify the price that a new drug can charge. Nevertheless, on the basis of this and other trials, Optimer has completed its New Drug Application, and the FDA’s Anti-Infective Drugs Advisory Committee will review it at a meeting in April.
Well, wow. National legislators stand up to oppose the use of tax revenues to subsidize large-scale confinement pig farms out of concern for food safety and antibiotic resistance, declaring that they are “going to war in defense of pigs.”
In Europe, though.
At the European Parliament today, three national representatives — Janusz Wojciechowski of Poland, José Bové of France and Dan Jørgensen of Denmark — declared their opposition to industrial-scale swine agriculture, positioning themselves for a fight over the European Union’s Common Agriculture Policy, which is up for revision this summer.
Jørgensen represents the country that has done the most to place controls on agricultural antibiotic use; Bové is a farmer and political organizer who famously destroyed a McDonald’s by driving a tractor through it; and Wojciechowski is the son of pig farmers who wrote on his blog today:
Chcemy poruszyć sumienia posłów i doprowadzic do likwidacji tego typu “fabryk miesa” w Unii Europejskiej, no czywiscie takze w Polsce, gdzie takich fabryk jest juz ponad sto.
Chcemy doprorowadzic do tego, aby wielkie fermy nie były wspierane środkami europejskimi, aby wstrzymać lokalizacje nowych obiektów, po czym stopniowo likwidować te, które już istnieją.
Chcemy, żeby na miejsce fabryk miesa powróciła normalna hodowla świń.
We want to move the conscience of members and lead to the liquidation of this type of “meat factories” in the European Union, also in Poland, where such plants are already over a hundred.
We want to ensure that large farms are not supported by the European funds to stop the locations of new facilities, then gradually eliminate those that already exist.
We want “meat factories” returned to normal breeding of pigs. (via GoogleTranslate)
As I’ve written before (long archive here and here),the MRSA strain ST398 arose on Dutch pig farms in 2004, among pigs that had been given prophylactic doses of antibiotics, especially tetracycline. It has since spread through the EU, Canada and the United States, affecting not only farm workers and veterinarians, but also hospital patients with no connection to agriculture.
(Self-promotion alert: This may be a good time to tell you that my book SUPERBUG: The Fatal Menace of MRSA, which tells the full story of the emergence and spread of ST398, has just been released in paperback.)
In advance, this morning the trade paper Farming UK wrote this about the planned European Parliament announcements:
(Members of the European Parliament) will hear evidence that European taxpayers’ money is being used by the European Bank for Reconstruction and Development, together with Common Agriculture Policy payments, to subsidise industrial pig farming even though there is increasing concern over the impact on human health. With a vote this summer over reforms to the Common Agricultural Policy, MEPs will come together to take a stance against the crisis in agriculture with critically low prices for pork, poor labelling, and widespread disregard for animal welfare laws.
MEPs and NGOs will condemn the overuse of antibiotics in factory farms which has led to the emergence of antibiotic-resistant bacteria such as MRSA and ESBL E. coli. A recent report by the Dutch Food Standards Agency estimated that one third to one half of all antibiotic resistance in human diseases in the Netherlands derives from farm antibiotic use. American scientists recently found that flies and cockroaches from intensive pig farms carry bacteria resistant to the same antibiotics routinely used in pig farming, and warned that the insects were likely to be able to spread the disease from the farms to local people.
In both medicine and agriculture, Europe has been ahead of the US in addressing concerns about antibiotic resistance. This morning’s announcements are yet more evidence of just how far ahead they are.