Oct 17, 2003 (CIDRAP News) – The US Department of Agriculture (USDA) says the prevalence of Listeria monocytogenes in tested samples of ready-to-eat (RTE) meat and poultry products is down 25% for the first 9 months of this year compared with last year.
Further, Listeria prevalence in tested samples this year is about 70% lower than it was before the Hazard Analysis and Critical Control Points (HACCP) system for controlling pathogens in meat was implemented in 1998, the USDA's Food Safety and Inspection Service (FSIS) reported in a news release.
From January through September, 0.75% of RTE product samples tested positive for L monocytogenes, compared with 1.03% in 2002, the FSIS said. The agency's figures for previous years indicate a fairly consistent decline in prevalence: 1.32% in 2001, 1.45% in 2000, 1.91% in 1999, 2.54% in 1998, 2.25% in 1997, and 2.91% in 1996.
FSIS Administrator Dr. Garry L. McKee commented, "FSIS has taken aggressive action to prevent contamination of ready-to-eat meat and poultry products by Listeria monocytogenes and our testing is verifying that our programs are effective."
The 0.75% figure for this year is based on tests of 4,111 samples, FSIS spokesman Matt Baun told CIDRAP News. He said the agency tests about 7,000 samples of RTE products at processing plants annually. The testing program does not include retail stores.
While FSIS test results indicate trends, the testing programs are not designed to identify statistically significant changes from year to year or to estimate the actual nationwide prevalence of pathogens in RTE products, according to FSIS reports.
The FSIS announcement comes about a year after a listeriosis outbreak in the Northeast that caused 7 deaths and three miscarriages and prompted the FSIS to conclude that some plants were not doing enough to control the pathogen. As a result of that outbreak, the agency announced in November 2002 that it would increase testing at plants that produced hot dogs and deli meats without doing their own environmental testing for Listeria or sharing environmental test results with the FSIS. Previously the agency had tested RTE products but not food-contact surfaces and equipment.
The Listeria report also comes about 2 weeks after the advent of new USDA rules requiring meat processing plants to take specific steps to control Listeria. The new rules, which were announced in June and took effect Oct 2, are the result of a formal Listeria risk assessment that took about year.
As announced in June, the new rules require plants to choose one of three approaches for controlling Listeria in RTE products. The choices include using both a post-cooking treatment (such as steam heating) and a chemical growth inhibitor, using one of those two measures, or using general sanitation only. Plants using the less stringent control options will be inspected more often, according to the FSIS.
The declining levels of Listeria reported by the FSIS parallel a reported decline in listeriosis cases in recent years. Last April, the Centers for Disease Control and Prevention estimated that cases dropped 38% between 1996 and 2002, on the basis of figures from the FoodNet (Foodborne Diseases Active Surveillance Network) program. FoodNet, which includes areas accounting for about 13% of the US population, reported a listeriosis incidence of 0.27 laboratory-confirmed cases per 100,000 population in 2002.
FSIS news release
FSIS explanation of microbiologic testing program for RTE meats
FSIS Listeria rule effective Oct 2, 2003