I’ve added Aetiology, a blog maintained by Tara C. Smith, PhD, assistant professor of epidemiology at University of Iowa and supervisor of the team that found the first evidence of MRSA in US pigs. She’s currently running a list of posts on summer science reading. Enjoy.
Via a journal that’s new to me — the Acta Veterinaria Scandinavica, the open-access journal of the Veterinary Associations of the Nordic Countries — comes an amazing review of the prevalence of antibiotic resistance in cattle in 13 European countries. Based on 25,241 isolates collected over three years, Denmark, Britain, the Netherlands, Norway, Sweden and Switzerland do well, but “many isolates from Belgium, France, Italy, Latvia and Spain were resistant to most antimicrobials tested.“
Most resistant pathogen: E. coli. MRSA is present as well:
Of major concern is the level of resistance to oxacillin and 3rd generation cephalosporins (i.e. ceftiofur) in S. aureus. The prevalence of oxacillin resistance in Spain (3.7%) and France (8.3%) and the resistance towards cephalosporins in Spain (0.9% in 2004) and France (4.2% in 2002; 1% in 2003) indicate the presence of methicillin resistant S. aureus (MRSA) in these two countries.
The authors ascribe the differences among countries to different patterns of antimicrobial use by veterinarians and stress that it is time for veterinarians to begin using measurements of local resistance patterns (in human medicine, an “antibiogram”) before prescribing.
Cite coming when the Acta site is updated. UPDATE: The paper is here; cite is: Hendriksen, RS et al. Prevalence of antimicrobial resistance among bacterial pathogens isolated from cattle in different European countries: 2002-2004. Acta Veterinaria Scandinavica 2008, 50:28doi:10.1186/1751-0147-50-28.
I wasn’t aware that this same set of authors (Hendriksen, RS et al.) just a few weeks ago published a similar review of antimicrobial resistance in pigs in Europe. It looks at several bacterial species in pigs, but unfortunately for our purposes, no S. aureus.
There will be a bit of a blog break, as I’m traveling for a week. But here as a walk-off is an excellent post from the marvelous public-health blog Effect Measure about the complexities (to be kind) of food companies declaring antibiotic use in food animals.
Very short version of the story: Massive chicken producer Tyson advertised its chickens as being “raised without antibiotics”; the chicken eggs were actually being treated with gentamicin before hatch (therefore technically not being “raised”; the US Department of Agriculture objected, then backed down, then objected again after Tyson’s competitors acted on their own.
Tyson announced it is “voluntarily” withdrawing the label. Which is more than the USDA did, apparently, its hand having been forced by Tyson’s competitors organized into the Orwellian-named Truthful Labeling Coalition (including Perdue Farms Inc., Sanderson Farms Inc. and Livingston, California-based Foster Farms). Perdue and Sanderson had sued over a label they considered “clearly false and misleading,” and a federal judge agreed, ordering Tyson to stop them from running any advertisements with the claim last month. Now, belatedly, the USDA is acting.
The entire post is worth reading, as is Effect Measure (which is running on a “summer schedule” and therefore posting only once a day, thus making us all look bad. Hmm, perhaps a Public Health Blog Truthful Labeling Coalition is in order…)
A posting on the international disease-alert mailing list ProMED led me to a scientific abstract presented at a European meeting this spring on the ST 398 MRSA strain. It adds another, quite unnerving piece to the emerging interplay of MRSA in pigs, humans who have close contact with pigs, humans who have contact only with pig meat, and health-care workers who treat those humans.
Brief precis: About a year ago, Dutch health authorities discovered that a patient who had come in for surgical debridement of a diabetic foot ulcer had an unrecognized MRSA strain in that ulcer. Subsequently, they discovered that four other patients and five health-care workers in the same institution were carrying the same strain. None of the patients reported any contacts with pigs (or calves, which have also been found to carry the strain). One of the health-care workers lived on a farm that raised pigs, but said that she had no contact with the animals in her daily life; nor did her partner.
The authors conclude:
While the source is not fully established it could be the HCW living on a pig farm. This outbreak makes clear that transmission on a larger scale can occur, even with NT-MRSA.
(Hat-tip to Helen Branswell of the Canadian Press for telling me about the ProMED report. And a note to loyal readers: The “MRSA in meat” story is being picked up by some US newspapers. Doesn’t it feel good to know you’ve been reading about the issue here for months? And if you’re a reader of Helen’s work, months more? Of course it does.)
Dr. J. Scott Weese of the Ontario Veterinary College (author of many important papers, discussed in many posts here, on MRSA in food and companion animals) has started a blog on animal-health issues. Here is a recent post on tracking down the source of a MRSA infection when there is a pet in the house.
The blog is called Worms and Germs and I’ve added it to the blogroll at right.
It turns out that European governments — in contrast to the United States — are taking very seriously the emergence of MRSA in food animals and its potential for transfer to humans. (For background, posts here, here, here and here.)
How seriously? They’re doing a sampling survey of pigs on farms across the European Union, at a cost of about $3 million in EC funds, with matching funds expected from each government.
The MRSA survey piggybacks (sorry) on a year-long survey of Salmonella incidence that the EC called for in September 2007. But in December, following publication of several significant papers about the ST 398 MRSA strain in pigs and pig farmers, the EC Directorate-General for Health and Consumer Protection pushed for an addition to the Salmonella study: a same-time sampling for the presence of MRSA strains in pig operations across 29 countries.
The sampling is taking place from January to December of this year, with results mandated by mid-2009, though individual country authorities may release data earlier if they choose. (In the wake of the finding of three ST 398 cases apparently caused by retail meat in the UK, the Soil Association has called on the British government to release whatever data it has ASAP. Before the EC decision, the UK government had refused to test its pigs; cf. these House of Lords minutes.)
Of note: The Soil Association is pressing the argument that ST 398 has developed in the setting of widespread use of antibiotics in food animals, and contends the strain’s arising in the Netherlands is especially alarming because
they have some of the lowest animal-antibiotic use rates in the EC it illustrates the difficulties that even a society conscientious about antibiotic overuse can have keeping track of veterinary applications. The Netherlands has been successful limiting overuse in humans, but has found controlling veterinary use much more of a struggle. (Thanks to the Soil Association for correcting my misunderstanding!)