The food chain situation with MRSA examined
We don’t add antibiotics to baby food and Cocoa Puffs so that children get fewer ear infections. That’s because we understand that the overuse of antibiotics is already creating “superbugs” resistant to medication. Yet we continue to allow agribusiness companies to add antibiotics to animal feed so that piglets stay healthy and don’t get ear infections. Seventy percent of all antibiotics in the United States go to healthy livestock, according to a careful study by the Union of Concerned Scientists — and that’s one reason we’re seeing the rise of pathogens that defy antibiotics.
via Op-Ed Columnist – Pathogens in Our Pork – NYTimes.com.
This well known science blogger suggest we not be too tentative about ST398.
I’m always loath to criticize mainstream discussions of the antibiotic resistance, particularly when the link between antibiotic use in agriculture and antibiotic resistance is raised. But, while NY Times columnist Nicholas Kristof meant well, he missed the mark.
In his column about MRSA ST398, he describes things that might happen. Here’s one example:
Public health experts worry that pigs could pass on the infection by direct contact with their handlers, through their wastes leaking into ground water (one study has already found antibiotic-resistant bacteria entering ground water from hog farms), or through their meat, though there has been no proven case of someone getting it from eating pork. Thorough cooking will kill the bacteria, but people often use the same knife to cut raw meat and then to chop vegetables. Or they plop a pork chop on a plate, cook it and then contaminate it by putting it back on the original plate.
The problem I have with Kristof’s column is that MRSA ST398 isn’t a hypothetical. The reason the spread of MRSA ST398 into the healthcare system scares the crap out of me isn’t that it might happen: it’s already happened. We already have documented evidence from the Netherlands, where ST398 has started to show up in the healthcare system in agricultural regions of the country. And in Sweden, ST398 is present in the community.
via Mike the Mad Biologist : Kristof on MRSA: Good, but There’s Better Evidence.
This is another helpful article from the writer putting ST398 at the centre of media attention. See link below for full story.
Some readers have suggested that I’m picking on pigs (in my last couple of columns), since other animals can also carry MRSA. That’s true, but there are a couple of reasons for focusing on hogs.
One is that hogs produce vast amounts of waste, creating important sanitation problems. The town I reported my first column from, Camden, Indiana, has a population of a bit more than 500, and a sewage system to match. But around it are more than 50,000 hogs, producing more waste than a city of 100,000 people, and there’s no sewage treatment system for those hogs. Instead, the waste sits in ponds and eventually seeps into ground water. No city of 100,000 would ever go without a sewage system, but that’s routine for clusters of hog operations. And sanitation is one route by which diseases including MRSA can spread. There’s some evidence that the business model of industrial hog operations is essentially to save money by externalizing the sanitation costs on the public.
via When Boars Grope Sows…. – Nicholas D. Kristof Blog – NYTimes.com.
Kristof blames the overuse of antibiotics in healthy animals for the antibiotic resistance in both people and animals:
[T]he central problem here isn’t pigs, it’s humans. Unlike Europe and even South Korea, the United States still bows to agribusiness interests by permitting the nontherapeutic use of antibiotics in animal feed. That’s unconscionable.
The Pultizer-prize-winning Kristof is no foe of farmers. He grew up on a farm and has tuned in to food. He called for a Secretary of Food rather than a Secretary of Agriculture and followed-up after Vilsack’s appointment suggesting a Deputy Secretary of Food.
Still, over at ScienceBlogs Mike the Mad Biologist says there’s better evidence:
The problem I have with Kristof’s column is that MRSA ST398 isn’t a hypothetical. The reason the spread of MRSA ST398 into the healthcare system scares the crap out of me isn’t that it might happen: it’s already happened. We already have documented evidence from the Netherlands, where ST398 has started to show up in the healthcare system in agricultural regions of the country. And in Sweden, ST398 is present in the community.
These are countries with reasonably good antibiotic use policies, so I’m not exactly optimistic. I’m glad Kristof raised the issue, but the reflexive conservative denialists will attack the column, when he could have provided much stronger evidence.
via MRSA ST398 & the Overuse of Nontherapeutic Antibiotics.
Flies, already blamed for spreading disease, may help spread drug-resistant superbugs from chicken droppings, researchers reported on Monday. They matched antibiotic-resistant enterococci and staphylococci bacteria from houseflies and the litter found in intensive poultry-farming barns in the Delmarva Peninsula region of Delaware, Maryland and Virginia. The findings, reported in the journal Science of the Total Environment, may help explain some of the spread of drug-resistant bacteria.
via Flies may be spreading MRSA from fowl feces – Infectious diseases- msnbc.com.
Purdue University experts said a New York Times opinion piece this week that tried to establish pigs as a source of MRSA infection for humans is “highly speculative.”
MRSA, (methicillin-resistant Staphylococcus aureus), or antibiotic-resistant staph, can be found anywhere in nature, according to Paul Ebner, a livestock microbiologist. While he said there has been an increase in the number of these infections and that pigs and other animals can be carriers, the vast majority of infections come from skin-to-skin contact with infected humans.
Making assumptions based on limited studies or information is a big jump and there is no proof to link MRSA in humans to pigs and pig operations at this time, said Ching Ching Wu, professor of veterinary pathobiology and head of microbiology in Purdue’s Animal Disease and Diagnostic Laboratory. Wu said there is more scientific evidence to support the spread of MRSA among humans and from humans to animals rather than from animals to humans.
A University of Iowa study mentioned in the Times column was a pilot study that looked at only two farms, and only one of them had the organism. Another Dutch study was also inconclusive, according to the Purdue experts.
via Purdue Experts On Livestock & Antibiotic Resistance – Cattle Network.
Note that this was the mild version.
Researchers at Rhode Island Hospital, led by infectious diseases specialist Leonard Mermel, DO, ScM, set out to determine if retail beef, chicken and pork is contaminated with MRSA, vancomycin-resistant enterococci (VRE) and other antibiotic-resistant bacteria. To do so, meats from 10 supermarkets and butcher shops in the greater Providence area were obtained for a total of 36 samples (12 each of beef, chicken and pork).
Their findings indicated that only one of the 36 samples contained antibiotic-resistant bacteria, which was found in a sample of pork from one store. Of note, Staphylococcus aureus (methicillin-sensitive, not MRSA), was found in four of the 36 meat samples, which is consistent with previous reports. These findings do not indicate a cause for concern regarding meat purchased in the Providence area. The researchers, however, do urge the public to be sure to always cook meats to the recommended temperatures. This will reduce risk of illness if any bacteria is present.
Meat Evaluated For MRSA, VRE And Other Organisms In First Of Its Kind Study.
The suggestion that stable dust is part of the infection pattern is a key insight of this story.
We compared the prevalence of human and animal methicillin-resistant Staphylococcus aureus (MRSA) at pig farms in The Netherlands, and related this to individual and farm-level characteristics. More than half of the farms investigated (28/50) had MRSA in pigs or stable dust and about one third (15/50) of person(s) were identified as MRSA carriers. Human carriage was found only on farms with MRSA-positive pigs or dust. MRSA strains in human samples were the same spa-type as found in pigs and all were not typable by pulsed-field gel electrophoresis (NT-MRSA). Multivariate analyses showed that risk factors for human MRSA carriage were: working in pig stables (OR 40, 95% CI 8-209) and the presence of sows and finishing pigs (OR 9, 95% CI 3-30). Veterinary sample collectors sampling the pigs showed transient MRSA carriage only during the day of the farm visit. Working in pig stables with MRSA-positive pigs poses a high risk for acquiring MRSA, increasingly so when contact with live pigs is more intensive or long lasting.
HighWire Press — Medline Abstract.
Vets will be geting human MRSA via companion animals and acting as petri dishes for interaction with the pig varient. Not a good scenario
Seemingly healthy animals are sometimes colonized with the bacteria, and there is evidence humans can both transmit it to animals and become colonized or infected from them. Infections have been reported in horses, dogs, cats, pet birds, cattle, and pigs, the backgrounder states.
The publication says veterinarians are at risk of becoming MRSA reservoirs. About 6.5 percent of practitioners who attended the 2005 American College of Veterinary Internal Medicine Forum and volunteered for testing were colonized with MRSA. None had been recently hospitalized or previously had the infection diagnosed.
Of those volunteers, about 4.4 percent of small animal practitioners and about 15.6 percent of large animal practitioners were colonized.
About one percent of the general public is colonized with MRSA and 30 percent with Staphylococcus, according to information from CDC spokeswoman Nicole Coffin.
The AVMA backgrounder says veterinarians need to practice proper hygiene and educate others who come into contact with infected animals how to minimize risks.
To read the publication, go to www.avma.org, click on the Reference tab, and follow the Animal Health link. FAQ sections are available through links on the side of the full article.
AVMA backgrounder cautions practitioners about risks of MRSA – November 15, 2008.
