Posted: March 22nd, 2011 - 9:58am
Source: Meatingplace

CHICAGO -- The beef industry is working to get ahead of emerging issues involving multiple drug-resistant (MDR) salmonella and non-O157 Shiga-toxin producing E. coli (STEC) in ground beef, experts said here Thursday at the North American Meat Processors Association’s Management Conference.
The discussion on MDR salmonella, or those strains that are resistant to between two and 10 antibiotics, came a day after a task force of public health agencies including the Centers for Disease Control and Prevention published a report identifying drug-resistant pathogens as a growing threat.
Meanwhile, talk of non-O157 STECs surrounded narrowing the focus to those strains that cause illness in humans and producing reliable methods of testing as the federal Office of Management and Budget considers finalizing USDA enforcement policy.
Happy with the industry’s performance in controlling E. coli O157:H7, the agency is putting emphasis on other pressing pathogens of the day and preventing contamination during dressing procedures.
In a study by USDA’s Agricultural Research Service published February 2009, researchers collected 4,100 commercially produced ground beef samples from 18 plants in seven regions across the country over a two-year period to assess salmonella presence in ground beef. They found that the overall prevalence of salmonella strains was 4.2 percent. The prevalence of MDR salmonella was 0.6 percent. Meanwhile, more than 94 percent of the pathogens were found at low concentrations, at less that 2 coliforms per gram of product.
Mohammad Koohmaraie, former director of ARS’s Meat Animal Research Center and now CEO of the meat division of a private consulting and testing firm, who worked on the study with Joseph Bosilevac, said prevalence is low, but the industry should address the matter before it becomes a regulatory issue.
Current interventions used to reduce non-MDR strains will work on MDR strains, Koohmaraie said. The hides and lymph nodes of cattle, particularly cull dairy cows that have had long-term exposure to antibiotics, are the likeliest of sources of contamination. As such, proper hide removal during dressing and best possible removal of lymph nodes during fabrication will be key, he said.
In a later presentation, Dan Engeljohn, chief policy writer for USDA’s Food Safety and Inspection Service, also called for greater attention to removal of lymph nodes and hides to combat salmonella prevalence.
From 1990 to 2007 there were only 23 outbreaks of foodborne illness caused by non-O157 STECs. But, as Justin Ransom, assistant vice president of food protection and government affairs at OSI Industries, pointed out, an outbreak of E. coli O26 – one of six non-O157 STEC strains known to cause illnesses in the United States --associated with ground beef produced by Cargill’s Wyalusing, Pa., plant accelerated the issue for the industry. It was the first non-O157 STEC outbreak linked to beef.
Ransom said non-O157 STECs aren’t known to be as virulent as O157:H7, but they are difficult to identify during testing because of their vulnerability to current antimicrobials used in the enrichment phase.
He said FSIS will likely require testing for non-O157 STECs in the future, but the industry should address the issue proactively rather than repeat the reactive approach it took O157:H7 during the early 1990s.
Responding to an attendee who suggested that the issue of non-O157 STECs remains an academic matter, Ransom said, “Until [non-O157 STECS] become an adulterant, it is academic. But once [they do become an adulterant], it becomes regulatory.”