iOS app Android app More

Featuring fresh takes and real-time analysis from HuffPost's signature lineup of contributors
David Kirby

GET UPDATES FROM David Kirby
 

MRSA in Meat: Why No Recall?

Posted: 09/15/10 08:00 AM ET

Next week, Congress will hold hearings on the recent recall of more than half a billion eggs infected with salmonella -- all of them from two factory farms in Iowa.

That recall, though voluntary, was essential: Salmonella can make you very sick, though if treated on time, it is rarely fatal.

But that's not the case for MRSA (Methicillin-resistant Staphylococcus aureus), or drug-resistant staff infection. In 2005, U.S. hospitals treated more than 278,000 MRSA cases. Nearly 100,000 people faced life threatening illness and 18,650 died: 50 percent more than the number of AIDS death that year.

This evolving superbug sprang from the overuse of antibiotics -- not only in hospital settings, but also in animal agriculture, which consumes an estimated 70 percent of all antibiotics sold in this country. Most of those drugs are given at low dose to promote animal growth and prevent disease, a practice that encourages the emergence of multi-drug resistant bacteria.

Now MRSA is showing up in random samples of raw pork sold in supermarkets, and to a lesser extent in beef and chicken. Yet these potentially deadly cuts of meat -- unlike the salmonella-tainted eggs -- have never been yanked off the shelves.

Why not? Because no government inspector has ever tested live animals or meat for MRSA.

Fortunately, other people have stepped in where government has failed. A University of Iowa study published last year found that one Midwestern hog factory farm was a nonstop breeding pool for the deadly disease: More than a third of all adult swine and 100 percent of the younger pigs aged 9 and 12 weeks were carriers, as were 64 percent of the workers. A second hog factory had zero MRSA infections.

"Our results show that colonization of swine by MRSA was very common in one of two corporate swine production systems," said lead author Tara Smith, adding that MRSA transmission on hog factories, "could complicate efforts to reduce MRSA transmission statewide and beyond."

The infected herd, incidentally, had twice as many hogs as the uninfected one, and ALL of those little piggies, presumably, went to market.

Meanwhile in the Netherlands, one-in-five human MRSA cases were caused by a "livestock associated" strain of the bug, and one study of 26 Dutch pig farmers found a MRSA rate 760 times greater than among patients admitted to Dutch hospitals.

But what about meat sold in stores? Last year, researchers at Louisiana State University tested samples obtained from Baton Rouge supermarkets and found that 5.5 percent of the pork and 3.3 percent of the beef was positive for MRSA. Five out of the six infected pork samples were "chain-branded meats." Equally unsettling, even more samples tested positive for non-methicillin resistant staph: 20 percent of the beef and a whopping 45.6 percent of the pork.

Eating meat with nonresistant staph can cause food poisoning from "heat-stable" toxins, the paper said, while "the presence of MRSA in meats may pose a potential threat of infection to individuals who handle the food."

Does the "presence of MRSA in meats" come directly from the presence of MRSA in factory farm animals? It would be reasonable to assume so, but surprisingly, the LSU study said that probably wasn't the case.

Most animals are infected with a very specific "livestock associated" strain of MRSA, but the meat samples in the stores were found with human-related MRSA, and not the livestock strain.

And even though pigs can also carry the same human-associated strains of MRSA found in the retail pork, the authors concluded that "humans, not animals, are the likely contamination source. They added that efforts are needed "to prevent the introduction of MRSA from human carriers onto the meats they handle."

Really? Just blame the workers? I'm not so convinced.

To begin with, LSU is part of the "Land Grant University System," which receives millions of dollars for agricultural research from the pro-agribusiness USDA and from agribusiness itself. Moreover, the study was "limited in geographical region, survey period and sample size," the authors said. "Further studies at the farm and retail levels involving larger sample sizes over time are needed."

But looking at it from a human health point of view, does it really matter where the MRSA came from? It's there, and the government is doing nothing to stop it.

So why all the fury over salmonella in eggs, but no recalls of meat with MRSA?

I asked that question of the FDA: They don't regulate meat, they said, I should ask the USDA. I asked the USDA -- repeatedly -- and they never got back to me. Then I wrote to the National Pork Producers Council, and they referred me to a study out of Canada.

The MRSA rates in Canadian retail meat were quite high: 13 percent of the pork chops (nearly 1-in-7) and 6.3 percent of the ground pork was contaminated, along with 5.6 percent of the beef and 1.2 percent of the chicken.

But like the LSU study, this paper also found only human-related bacteria in the meat, and not the livestock associated strain. "If MRSA in meat is a direct reflection of MRSA in food animals, frequent isolation of (livestock-associated) strains would be expected," the Canadian study said.

Again, workers, and not factory farm animals, were likely to blame, this study asserted: "The potential role of slaughterhouse and food-processing personnel, and the food processing environment require consideration."

It was funded in part by the (U.S.) National Pork Board.

Meanwhile, the authors wrote that bacteria counts were generally low, though they added that, "while low levels may be less concerning, they should not be dismissed." The risk from eating contaminated meat was also low, "although it is plausible that ingestion could result in gastrointestinal colonization and the potential for subsequent infection or transmission." Moreover, touching one's nose after handling the meat "could plausibly result in nasal colonization," and contact with skin sores "could potentially result in infection."

MRSA is not always serious. A healthy person can be infected without showing symptoms, which usually appear as small pimple-like bumps that become painful, pus-filled boils. Most cases remain on the skin and respond to treatment. But nastier strains are evolving; they are more invasive, rapidly infect organs, and can induce system-wide sepsis, toxic shock and "flesh-eating" pneumonia.

So why shouldn't contaminated meat be recalled? I wrote again to the pork producers' council for further comment, and here is what I was told:

You have the study, which should answer your questions. And while your questions may be simple, the answers are not. Besides, you have an agenda. I thought your name was familiar; I read your book.


Dave Warner
Director of Communications
National Pork Producers Council

He's right, I do have an agenda. My agenda is that consumers should not have to worry about bringing home any food contaminated with a drug-resistant superbug that could possibly result in system-wide sepsis, toxic shock and flesh-eating pneumonia.

David Kirby is author of "Animal Factory, the Looming Threat of Industrial Pig, Dairy and Poultry Farms to Humans and the Environment." (St. Martin's Press)