A recent study by the Arizona-based Translational Genomics Research Institute (TGRI) has reportedly identified Staphylococcus aureus in 47 percent of meat and poultry samples obtained from retail stores, with 52 percent of the contaminated samples testing positive for multidrug-resistant S. aureus. Andrew Waters, et al., “Multidrug-Resistant Staphylococcus aureus in U.S. Meat and Poultry,” Clinical Infectious Diseases, April 2011. According to a summary of the study, which received funding from the Pew Charitable Trusts, researchers collected 136 samples of ground beef, chicken breasts and thighs, ground pork and pork chops, and ground turkey and turkey cutlets from 26 retail stores in Chicago, Washington, D.C., Fort Lauderdale, Los Angeles, and Flagstaff.

The results purportedly indicated that S. aureus contaminated “a substantial portion of samples from all meat and poultry types (37-77%), with a notable 52% of isolates being multidrug resistant” to antimicrobials such as tetracycline, ampicillin, penicillin, and erythromycin, among others. “The distinct S. aureus populations on each product type suggest that food animals are the predominant source of contamination,” concluded the researchers, who have recommended adding multidrug-resistant S. aureus to “the list of antimicrobial-resistant pathogens that routinely contaminate our food supply.” See TGRI Press Release, April 15, 2011.

Although the study authors also noted that “the public health relevance of this finding is unclear,” their work has attracted attention from federal regulators, infectious disease experts and the media. As one Food and Drug Administration (FDA) spokesperson told the press, “FDA has been monitoring the situation… [and] continues to work with [the Centers for Disease Control and Prevention] and [U.S. Department of Agriculture] to better understand this issue.” See MSNBC.com, Reuters and Law360, April 15, 2011.

The American Meat Institute, however, has since called the study misleading. “Despite the claims of this small study, consumers can feel confident that meat and poultry is safe,” AMI President James Hodges said in an April 18, 2011, statement. “Federal data show that S. aureus infections in people that are caused by food are uncommon. CDC data also show that foodborne illnesses as a whole are declining due to our growing scientific knowledge about how to target and destroy bacteria on meat and poultry.”