“When you’re only No. 2, you try harder,” was Avis’ slogan for 50 years. It could be picked up at some point in the future by E. coli 026, the pathogen that has sickened Chipotle customers in nine states. It’s been just a dozen years since 026 began to get recognition as a new killer strain of E. coli that could become a serious health threat in the United States. To illustrate the point, Dr. Mark Stevens of the Institute for Animal Health in the United Kingdom said a decade ago that 026 was already as dangerous as E. coli O157. When 026 came along, the Shiga toxin-producing Escherichia coli (STEC) O157:H7 was well-known as a cause of bloody diarrhea, hemolytic uremic syndrome (HUS) and thrombotic thrombocytopenic purpura (TTP). E. coli O157 was banned from meat after the Jack in the Box outbreak more than 20 years ago. ecoli026_406x250USDA expanded the ban just four years ago to include the six most common strains of non-O157 E. coli, a list that includes 026, along with O45, O103, O111, O121 and O145. E. coli strains begin in cattle intestines, and 026 is said to have come from Europe. And, like O157, the 026 variety also spreads to humans through fecal contamination. Some E. coli 026 strains are more virulent than others. Scientists have isolated as many as 272 strains, and some of them are second only to O157 in causing illnesses that progress to more serious HUS, TTP, or renal failure. The 026 strain in the current outbreak has sent 20 people to hospitals, but as of Dec. 4, there were no reports of HUS, and nobody had died. In a way, Chipotle is lucky since the current outbreak could have been worse. The U.S. Centers for Disease Control and Prevention (CDC) said only two years ago in the journal Emerging Infectious Diseases that 026 often causes life-threatening complications, including HUS. CDC predicts that the non-O157 strains will all cause HUS more frequently in the future. And there’s already been research that the “clinical severity” and “outcomes for” children with O26 HUS will be worse than O157 HUS. There’s been no increase since Dec. 4 in either the number of confirmed cases or states involved in the E. coli 026 outbreak associated with Chipotle restaurants in nine states. However, neither CDC nor the U.S. Food and Drug Administration (FDA), nor any of the states involved, have been able to determine the source of the contamination. Here are some examples of how E. coli 026 has laid down tracks in the U.S. during the past five years:

  • On Feb. 15, 2012, CDC first announced an ongoing investigation into E. coli 026 illnesses linked to the consumption of raw clover sprouts consumed at Jimmy John’s restaurants in several states. By April, 29 cases were confirmed. Illness onsets ranged from Dec. 25, 2011, to March 3, 2012. Ill persons ranged in age from 9 years to 57 years old, with a median age of 26 years old. Eighty nine percent of the cases were female. No cases developed hemolytic uremic syndrome (HUS); however, 7 people were hospitalized. No deaths were reported. FDA and the states conducted a traceback that identified two separate sprouting facilities; both used the same lot of seed to grow clover sprouts served at Jimmy John’s restaurant locations. On Feb. 10, 2012, the seed supplier started notifying sprouting facilities that received this lot of clover seed to stop using it. Jimmy John’s restaurants announced that it was pulling sprouts from its restaurant menus.
  • An outbreak of E. coli O26 occurred in June 2011 among kitchen workers at Camp Lutherhaven, a summer camp located on Idaho’s Lake Coeur d’Alene. No campers were confirmed to be infected. The source of the outbreak among the kitchen workers was not determined.
  • An outbreak of E. coli O26 involved children who attended daycare programs in Ellensburg, WA. Foursquare Church Daycare and Preschool, Kids Learning Center, and Little Tot Town Day Care were the childcare programs affected by the outbreak. The first reported case was the only child who did not attend daycare. This child’s siblings who attended the Foursquare Church Daycare and Preschool were related to a child who attended one of the other daycare programs. The health department inspected the facilities and required that all children undergo stool testing. Children were not readmitted to the programs until their stool samples proved to be clear of E. coli O26.
  • Fifteen Kittitas County, WA, residents were infected with E. coli O26 in June and July 2010. Case patients ranged in age from 23 months to 7 years. One child was hospitalized. Fourteen of 15 children attended three childcare facilities, which were temporarily closed. How the pathogen originally got into the childcare center was never determined.

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