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Marler Blog Providing Commentary on Food Poisoning Outbreaks & Litigation

Multi-drug-resistant Staph Found in ¼ of meat samples starts food fight

staph-aureus-bacteria-16790-thumb-200x208-532.jpgThe internet is abuzz with the findings of a study funding by The Pew Charitable Trusts done by Lance B. Price, Ph.D., senior author of the study and Director of TGen’s Center for Food Microbiology and Environmental Health Nationwide. The study found that U.S. meat and poultry is widely contaminated Multi-drug-resistant Staph:

… Nearly half of the meat and poultry samples — 47 percent — were contaminated with S. aureus, and more than half of those bacteria — 52 percent — were resistant to at least three classes of antibiotics, according to the study published today in the journal Clinical Infectious Diseases.

This is the first national assessment of antibiotic resistant S. aureus in the U.S. food supply. And, DNA testing suggests that the food animals themselves were the major source of contamination.

Although Staph should be killed with proper cooking, it may still pose a risk to consumers through improper food handling and cross-contamination in the kitchen.

Researchers collected and analyzed 136 samples — covering 80 brands — of beef, chicken, pork and turkey from 26 retail grocery stores in five U.S. cities: Los Angeles, Chicago, Fort Lauderdale, Flagstaff and Washington, D.C. …

The American Meat institute hit back:

… A new Pew Commission-funded study misleads consumers about U.S. meat and poultry, which is among the safest in the world.

Authors of the new study, which involved a small number of samples from retail stores, claim that their findings suggest that a significant public health risk exists. However, federal data from the Centers for Disease Control and Prevention (CDC) show steady declines in foodborne illnesses linked to consumption of meat and poultry overall and indicate that human infections with Staphylococcus aureus ( “Staph”) comprise less than one percent of total foodborne illnesses.

It is notable that the study involved only 136 samples of meat and poultry from 80 brands in 26 retail grocery stores in five U.S. cities. This small sample is insufficient to reach the sweeping conclusions conveyed in a press release about the study. By contrast, when the U.S. Department of Agriculture studies the prevalence of bacteria, their work involves thousands of samples collected over long periods of time to ensure accuracy.

While the study claims that the many of the bacteria found were antibiotic resistant, it does note that they are not heat resistant. These bacteria are destroyed through normal cooking procedures, which may account for the small percentage of foodborne illnesses linked to these bacteria. As with any raw agricultural product, it is important to follow federal safe handling recommendations included on every meat and poultry package that urge consumers to wash hands and surfaces when handling raw meat and poultry and to separate raw from cooked foods to ensure that food is safe when served. …

Both groups are somewhat right. Dr. Price is right to raise the alarm that drug-resistant Staph is a risk to human health and that antibiotic use needs to be monitored for long-term health. He also correctly points to the real risk of cross-contamination in home and commercial kitchens. The AMI rightly points to the small sample size as less than persuasive. However, it also falls back on “just cook the shit out of it” argument that it always raises and ignores the real risk of bringing contaminated product into kitchens across the country. As I said the Los Angeles Times:

William Marler, a leading food safety attorney, said it was helpful to test meat samples available in stores because the U.S. Department of Agriculture’s Food Safety and Inspection Service focused its testing on meat production facilities.

“It’s good to see more people doing retail testing because it shows us that our meat is far less sanitary than most consumers would think,” he said.

I think more studies would make the issue clearer to both consumers, the AMI and the Government Regulators. We did a $500,000 study (5,000 samples) on non-O157 Shiga-toxin E. coli in hamburger and are just finishing up a smaller bacteria study (just in the Seattle area) on chickens – regular and organic. I think the more tests the better. Science is a good thing.

  • Doc Mudd

    Yawn. VIrtually this same survey was done in Europe a few years ago with similar results:
    This earlier study recognized the important role of cross-contamination in meat handling. They did some epidemiologically credible typing and surveying, instead of assuming source and jumping to rather unscientific conclusions like the TGen survey. I would have expected Pew’s $290,000 to have purchased them something a little less warmed-over and certainly a more professionally convincing presentation of their anti-farm spin, but maybe price inflation is compromising even activist cults these days.
    Oh well a quarter of a million bucks just doesn’t go as far as it once did. Pew is getting the strong kneejerk anti-agriculture buzz they wanted from well planned press releases, though, even if the rent-a-science is a little shopworn and shoddy. Kumbaya, campers. Be afraid, be very afraid!

  • Minkpuppy

    This story is so over-hyped it makes me ill. The sample size is hardly significant enough to draw the conclusions stated for one. Secondly, Stapylococcal food poisoning is so infrequently reported in meat that it isn’t even on FSIS’s radar. When it is associated with meat, it’s 100% due to improper handling after cooking.

    Thirdly, how can the researchers be sure the bacteria came from the animal? The people processing the meat could also very well be the source of the bacteria. What the article fails to mention is that most human beings (can’t remember the % my old microbiology profs loved to quote but it’s high) are currently carrying the Staph bacteria on their skin and in their nasal and mucous membranes. That means if they sneeze, or scratch their nose or rub their eyes, they probably will have it on their hands. Once it gets on the hands, it gets in the food if proper handwashing isn’t practiced. Sure, most plants have handwashing and glove changing policies but it frequently falls through the cracks when things get hectic.

    Whatever happened to responsible journalism?


  • Sam

    According to the AMI – “if you don’t look, you won’t find it”.
    Works for BSE, hoof and mouth disease, as well as bacterial pathogens!

  • You won’t like my 100 chicken study any better. Should be done in the morning. I think key is to give consumers more knowledge.

  • Staphylococcus toxin is not markedly affected by heating or freezing as it is heat stable. Even if the food is heated before eating, the poison in the food will cause illness although the heat has killed the bacterial cells.
    Do all toxins in food survive the cooking process?
    No, all toxins in food do not survive the cooking process. In fact, the botulism toxin caused by Clostridium botulinum can be inactivated by cooking. Boiling food for 10 minutes eliminates this toxin. However, many other toxins are heat stable. For example, Staphylococcus can produce toxins that are not destroyed by high cooking temperatures. To prevent toxins from developing in food, don”t leave food sitting out at room temperature for more than 2 hours. On a hot day (90° F or higher), food should not sit out for more than 1 hour.
    The toxin produced by staph bacteria is very heat-stable – so it is not easily destroyed by heat at normal cooking temperatures. The bacteria may be killed, but the toxin remains. Careful handling of food that is prepared ahead of serving is important. This is especially important with foods left over after one meal and planned to be used again at a later meal. Quick cooling and refrigeration, or holding at or above 140ºF, can help ensure that toxin has no chance to be formed.
    The toxin produced by staph bacteria is very heat-stable – it is not easily destroyed by heat at normal cooking temperatures. The bacteria themselves may be killed, but the toxin remains. Careful handling of food that is prepared ahead is important. This is especially important of foods left over after one meal and planned to be used again at a later meal. Quick cooling and refrigeration, or holding at or above 140 degrees F, can help ensure that toxin has no chance to be formed.

  • Chris Griffith

    I think many of the comments miss the real point –this is not that Staph causes food poisoning ( although it does and due to mild symptoms is very underreported such as the tuna sandwich someone I know had in San francisco that led to food poisoning and was never reported as was a tourist ) or the sample size –which although not large did suggest a trend –but the real issue is that multi drug resistant organisms ideally should not have been there, how did they get there ( does feeding animals antiobiotics play a role here , data from fluoroquinalone resistance in europe would suggest it did ) but that DRUG RESISTANCE SPREADS VERY EASILY and what are the implications for people acquiring infections with drug resistant organisms as we are rapidly running out of ones that some bacteria are sensitive to . For the good of all , not just in food poisoning , we need to limit the spread of antibiotic resistance and do everything to prevent it happening –including in the food production /processing industry –although some fear it is already too late