The bacteria Escherichia coli, mostly associated with fecal sources, has been used as a marker organism for years to detect contamination of water and foods with undesirable and pathogenic organisms. By itself E.coli is a harmless organism not known to pose any serious hazard to humans. Emergence of the virulent form of this species E. coli 0157:H7 changed the food safety scenario dramatically and it is one of the most dreaded pathogens by the food industry. Major focus was directed to make food products including fresh produce free from contamination by this strain through rigid and elaborate quality control procedures in the organized food industry. While tons of information has been generated during the last one decade on E.coli 015:H7, emergence of other virulent strains of this organism did not catch the attention of food safety experts till the recent episode in the US involving them tainting lettuce causing some damage.
"But as everyone focused on controlling that particular bacterium, known as E. coli O157:H7, the six rarer strains of toxic E. coli were largely ignored.Collectively, those other strains are now emerging as a serious threat to food safety. In April, romaine lettuce tainted with one of them sickened at least 26 people in five states, including three teenagers who suffered kidney failure. Although the federal government and the beef and produce industries have known about the risk posed by these other dangerous bacteria for years, regulators have taken few concrete steps to directly address it or even measure the scope of the problem.For three years, the United States Department of Agriculture has been considering whether to make it illegal to sell ground beef tainted with the six lesser-known E. coli strains, which would give them the same outlaw status as their more famous cousin. The meat industry has resisted the idea, arguing that it takes other steps to keep E. coli out of the beef supply and that no outbreak involving the rarer strains has been definitively tied to beef".
As comprehensive information on these new virulent strains is not available, regulators and the industry are in a fix regarding the need for making processing regimes more stringent to eliminate any risk posed by these microorganisms in meat products and refrigerated fresh produce. Meat industry is especially vulnerable because of innumerable past instances of meat contamination involving E.coli 015:H7 but it seems the industry is satisfied with the existing processing schedules that can also destroy other virulent strains. Probably this needs verification and confirmation by the safety authorities.