Between November 1992 and February 1993, the United States experienced one of the nation’s worst foodborne illness outbreaks in recent history. State health agencies, in collaboration with the Centers for Disease Control and Prevention (CDC), ultimately confirmed that more than 500 infections and 4 deaths were caused by consuming hamburgers tainted with E. coli O157:H7. This outbreak signaled the need for greater controls based on science to prevent foodborne illness and protect consumers.

The 1993 E. coli outbreak that affected hundreds of people in 4 states became the catalyst for the U.S. Department of Agriculture’s (USDA) Food Safety and Inspection Service’s (FSIS) decision to declare E. coli O157:H7, a harmful and potentially lethal strain of the bacteria, an adulterant in October 1994. Thus, under to the Federal Meat Inspection Act (FMIA), any raw ground meat that tests positive for O157 is declared adulterated and cannot be sold for human consumption.

FSIS subsequently began a sampling program to test for the pathogen in federally inspected establishments and retail stores. According to the CDC, the rate of E. coli O157 illnesses has been reduced by nearly 50 percent since 1997.

Despite these successes, food safety and public health advocates as well as lawmakers have been pressing FSIS to regulate six other strains of Shiga toxin-producing E. coli (STEC) the same way they do the well-known E. coli O157:H7 for years. Specifically, groups have urged FSIS to also declare the O26, O45, O103, O111, O121 and O145 serotypes, often referred to as the “Big Six,” as adulterants in beef. Those strains can cause severe illness and even death, especially among the most vulnerable members of the population such as young children and the elderly.

In September 2011, FSIS caused a stir in the meat industry when it announced its plan to institute  a zero-tolerance policy for the “Big Six” strains of E. coli that are responsible for human illness. The agency issued a Federal Register notice on September 20, 2011 indicating that raw, non-intact beef products that are intended for use in raw non-intact product, that are contaminated with STEC O26, O45, O103, O111, O121 and O145 will be adulterated within the meaning of 21 U.S.C. 601(m)(1) because they contain a poisonous or deleterious substance which may render them injurious to health.

When FSIS first made this announcement, it indicated that implementation of the testing program for these six additional strains would begin on March 5, 2012. However, FSIS delayed the start date for the program to June 4, 2012 in order to “allow industry time to implement any appropriate changes in food safety systems, including control procedures in their processes.”

As of today, FSIS’ new policy on six additional non-O157 STEC strains will be in effect. FSIS will now begin routinely testing raw beef manufacturing trim, a major component of ground beef, for the “Big Six.” As with E. coli O157:H7, products found to be contaminated with any of the six additional strains will be adulterated and, as a result, will not be allowed into commerce.