Posted: July 23rd, 2010 - 9:26am
Source: IFT


There have been significant strides in the reduction of Listeria monocytogenes (Lm) in the United States and other countries, due to aggressive food and equipment testing and zero tolerance for the bacteria, according to an expert panel at the 2010 Institute of Food Technologists (IFT) Annual Meeting & Food Expo®.
The United States undertook a concerted effort to reduce Lm in 2003 after two years of listeriosis outbreaks associated with ready-to-eat (RTE) meat and poultry products, said Daniel Engeljohn, PhD, deputy assistant administrator, Office of Policy and Program Development, and acting assistant administrator, Office of Data Integration and Food Protection, at the USDA Food Safety and Inspection Service.
Listeriosis is a serious infection caused by eating food contaminated with Lm. It can cause fever, muscle aches, and gastrointestinal symptoms such as nausea or diarrhea. If the infection spreads to the nervous system, it can cause headache, stiff neck, confusion, loss of balance or convulsions. It is especially dangerous for pregnant women, newborns, the elderly and adults with weakened immune systems.
Engeljohn said the stepped-up prevention efforts have led to several changes, including a risk-based verification testing program that uses a formula to determine a product’s risk and therefore the frequency of sampling. Previously, establishments were tested at random, without regard for the likelihood of contamination. In addition, testing was expanded to 10,000 products annually and also includes environmental and food contact surface samples.
Engeljohn said the change has been significant: In 1990, 4.61 percent of RTE products tested at random were positive for Lm. By 2009, that number declined to .38 percent.
Ewen C. D. Todd, a professor at Michigan State University and former head of the school’s National Food Safety and Toxicology Center, pointed to progress from the international community as well, stemming from a May 2009 meeting of experts. The participants in that workshop supported the Codex Alimentarius microbiological criteria for Listeria monocytogenes in RTE foods. A key component of that was to establish a zero tolerance for Lm in RTE products where the bacteria could grow.