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.
The severity of the April outbreak is spurring a reassessment.
“This is something that we really have to look at,” said Senator Kirsten Gillibrand, Democrat of New York, who plans to introduce a bill that would pre-empt the Agriculture Department by declaring a broad range of disease-causing E. coli to be illegal in ground beef and requiring the meat industry to begin testing for the microbes. “How many people do we have to see die or become seriously ill because of food poisoning?”
The issue will be one of the first faced by President Obama’s nominee to head the department’s food safety division, Dr. Elisabeth Hagen, who is scheduled to testify Thursday in her Senate confirmation hearing.
Part of the problem is that so little is known about the rarer E. coli strains, which have been called the “big six” by public health experts. (The term refers to the fact that, after the O157 strain, these six strains are the most virulent of a group of related E. coli.) Few food companies test their products for the six strains, many doctors do not look for them and only about 5 percent of medical labs are equipped to diagnose them in sick patients.
A physiological quirk of E. coli O157 makes it easy to test for in the lab, and many types of food are screened for it. The other E. coli strains are much harder to identify and testing can be time-consuming. The Agriculture Department has been working to develop tests that could be used in meat plants to rapidly detect the pathogens.
The lettuce linked to the April outbreak tested negative for the more famous form of E. coli, but no one checked it for the other strains, according to the Ohio company that processed it, Freshway Foods. It turned out that the romaine was infected with E. coli O145, one of the more potent of the six strains.
Emily Grabowski, 18, a student from Irondequoit, N.Y., ate some of the lettuce at her college dining hall and ended up in the hospital with kidney failure. Recuperating at home, she wonders now if she could have been spared her ordeal. “If they had tested it and they had caught it,” she said, “I wouldn’t have had the E. coli.”
Earthbound Farm, the nation’s largest producer of organic salad greens, is one of the few companies that does screen for the full range of toxic E. coli, and it has found a worrisome incidence of the rarer strains. Out of 120,000 microbial tests last year, about one in 1,000 showed the presence of unwanted microbes, mostly the six strains.
“No one is looking for non-O157 to the level we are,” said Will Daniels, Earthbound Farm’s senior vice president for food safety. “I believe it is really going to emerge as one of the areas of concern.”
Earthbound Farm was not involved in the April outbreak.
The O157 strain of E. coli is a frightening bug, causing bloody diarrhea and sometimes kidney failure, which can be fatal. Some of the six strains cause less severe illness, but others appear to be just as devastating as the O157.
The toxic E. coli bacteria originate in the guts of cattle, putting the beef industry on the front line. The O157 strain achieved notoriety in 1993 when four children died and hundreds of people were sickened by tainted hamburger sold at Jack in the Box restaurants. The next year, the Agriculture Department made it illegal to sell ground beef containing the O157 bacteria.
The beef industry now routinely tests for the O157 strain, but there is no regular testing for the other six strains.