Western U.P. Health Department is investigating a cluster of E coli O157:H7 cases who became ill over the Christmas holidays. Initially 3 local and 2 non-local cases were identified.

Investigation has led to the identification of two additional cases. Four of the cases were hospitalized; no deaths have occurred. The health department has determined that the likely source of the outbreak was an ill food-handler at The Ambassador, a Houghton restaurant. The restaurant owner and his staff have been working cooperatively with the health department’s Environmental Health division during the investigation. The restaurant remains open for business and there is no anticipated on-going risk of illness due to this outbreak.

“Such an investigation is a routine part of health department operations,” said Dr. Teresa Frankovich, M.D. “The cases came to light earlier this month and health department staff have been conducting interviews with the ill individuals to look for exposures they might have in common. All of the cases have now been linked through the restaurant.”

According to Dr. Frankovich, “Occasional, single cases of E coli diarrhea occur sporadically, but it is unusual to have a cluster of cases at the same time. Public health investigates clusters of disease or illness to make sure that there is no on-going risk of illness and to make sure prevention efforts are in place.”

Over at Outbreak Database, we have been keeping track of foodborne illness outbreaks – small and large – over the last 12 months.  Here are some of the more interesting E. coli Outbreaks:

Organic Pastures Unpasteurized, Raw Milk November 2011 – 5 Ill.  Raw milk products produced by Organic Pastures were recalled and quarantined by the state of California after five children were infected with the same strain of E. coli O157:H7 and drinking Organic Pastures raw milk. The children were residents of Contra Costa, Kings, Sacramento, and San Diego counties. The only common food exposure was the unpasteurized raw milk. Laboratory sampling failed to detect E. coli O157:H7. The recall was ordered strictly on the basis of the epidemiologic findings of the California Department of Public Health. Organic Pastures was implicated in an earlier outbreak of E. coli O157:H7, in 2006; the E. coli O157:H7 implicated in this outbreak was different than the strain implicated in 2006.

Cozy Vale Creamery Raw, Unpasteurized Milk Products November 2011 – 3 Ill.  Cozy Vale Creamery’s raw milk products were recalled due to their link to an outbreak of E. coli O157:H7 in Washington State that began in August. Cozy Vale Creamery’s whole and skim milk and cream were distributed through seven retail outlets in Pierce, Thurston and King counties. The recalled products had sell-by dates of December 6 or earlier. The Washington State Department of Agriculture discovered that locations in the milking parlor and processing areas were contaminated with the outbreak strain of E. coli O157:H7 bacteria. The milk products were sold at the farm store and at Marlene’s Market in Tacoma, two Olympia Food Co-Op locations in Olympia, Olympia Local Foods in Tumwater, Yelm Co-op in Yelm, Mt. Community Co-op in Eatonville and Marlene’s Market in Federal Way. Retail raw milk is legal to buy and sell in Washington State.

Multistate Schnucks Salad Bars, College Campuses Romaine Lettuce October 2011 – 60 Ill.  An outbreak of E. coli O157:H7 was first identified in the region around Saint Louis, Missouri. Cases were found in Saint Louis, Jefferson, Saint Charles, and Saint Clair counties and in the city of Saint Louis. The cases ranged in age from 1 to 94. At least six persons were hospitalized. Many of the cases had eaten items from salad bars prior to becoming ill. On October 28, Illinois state health officials revealed that they were investigating an illness that might be linked to the outbreak in Missouri. The link was not described. On October 31, health department officials acknowledged that Schnucks salad bars were a focus of the investigation, however other sources had not been excluded. Cases were identified in Minnesota and Missouri that were linked to college campuses. Additional cases were found in other states; the exposure location in these states was not described. Traceback analysis determined that a common lot of romaine lettuce, from a single farm, was used to supply the Schnucks’ grocery stores and the college campuses. The lettuce was sold to Vaughn Foods, a distributor, that supplied lettuce to the university campus in Missouri, but records were not sufficient to confirm that this lot was sent to this university campus. Preliminary findings of investigation at farm did not identify the source of the contamination.

Jaquith Strawberry Farm Strawberries September 2011 – 15 Ill.  An outbreak of E. coli O157:H7 was linked to eating fresh strawberries produced by Jaquith Strawberry Farm, in Oregon. The farm sold berries to buyers who in turn distributed them to roadside stands and farmers’ markets in Multnomah, Washington, Clackamas, Yamhill, and Clatsop counties. The berries were sold in unmarked containers and were last distributed on August 1. Confirmed cases included residents of Washington, Clatsop, and Multnomah counties. Strawberries had not previously been implicated in an E. coli O157:H7 outbreak in the U.S. Ten percent of the environmental samples collected at the Jaquith Strawberry Farm tested positive for E. coli O157:H7. Those samples included deer feces; deer were suspected to be the source of the contamination. The outbreak strain was found in samples from fields in three separate locations.

Tyson Fresh Meats Ground Beef September 2011 – 4 Ill.  An outbreak of E. coli O157:H7 was associated with eating ground beef in a private home in Butler County, Ohio. A consumer sample of leftover ground beef was tested and confirmed the presence of the outbreak strain of E. coli O157:H7. On September 27, Tyson Fresh Meats issued a voluntary recall of 131,300 pounds of ground beef. The recall involved beef sold as Kroger brands at Kroger Company supermarkets; Butcher’s Beef at Food Lion supermarkets; and generic beef sold to Save-A-Lot, Spectrum Foods, Supervalu and the Defense Commissary Agency.

J & B Meats Ground Beef July 2011 – 2 Ill.  J & B Meats recalled ground beef after an investigation into two cases of E. coli O157:H7 linked the product to the illnesses. The beef had been sold to restaurants in the Cincinnati, Ohio, region.

McNees Meats and Wholesale LLC Ground Beef July 2011 – 9 Ill.  An outbreak of E. coli O157:NM was attributed to the consumption of ground beef produced by McNees Meats and Wholesale, LLC, of North Branch, Michigan. The implicated beef was sold to restaurants through a retail establishment owned by McNees Meats and Wholesale, LLC. Illnesses were reported from Genesee, Isabella, Lapeer, and Sanilac counties.

Jason’s Deli Guacamole April 2011 – 11 Ill.  Patrons of Jason’s Deli in Killeen, Texas, became ill with E. coli O157:H7 bacteria. The epidemiologic investigation revealed that guacamole made on April 13 was the most likely cause of the outbreak. The guacamole had been used as a sandwich spread for the California Club sandwich. The guacamole had likely become contaminated at the deli.

Palmyra Bologna Company Lebanon Bologna January 2011 – 21 Ill.  On March 23, the Centers for Disease Control announced that there was an investigation underway into an outbreak of E. coli O157:H7 that had been epidemiologically linked to the consumption of Lebanon bologna. The Palmyra Bologna Company, of Palmyra, Pennsylvania, issued a recall of the product on March 22. Lebanon bologna is a fermented, semi-dry, sausage. The suspect bologna was produced in December 2010, and had been shipped to five states.

The CDC reported today that 60 persons have been infected with the outbreak strain of E. coli O157:H7 in 10 states. The number of ill persons identified in each state is as follows: Arizona (1), Arkansas (2), Georgia (1), Illinois (9), Indiana (2), Kansas (3), Kentucky (1), Minnesota (3), Missouri (37), and Nebraska (1).

Among persons for whom information is available, illnesses began from October 10, 2011 to November 4, 2011. Ill persons ranged in age from 1 to 94 years, with a median age of 29 years old. Sixty-three percent were female. Among the 45 ill persons with available information, 30 (67%) were hospitalized, and 2 developed hemolytic uremic syndrome (HUS). No deaths have been reported.

The CDC reported today that 60 persons have been infected with the outbreak strain of E. coli O157:H7 in 10 states. The number of ill persons identified in each state is as follows: Arizona (1), Arkansas (2), Georgia (1), Illinois (9), Indiana (2), Kansas (3), Kentucky (1), Minnesota (3), Missouri (37), and Nebraska (1).

Among persons for whom information is available, illnesses began from October 10, 2011 to November 4, 2011. Ill persons ranged in age from 1 to 94 years, with a median age of 29 years old. Sixty-three percent were female. Among the 45 ill persons with available information, 30 (67%) were hospitalized, and 2 developed hemolytic uremic syndrome (HUS). No deaths have been reported.

Collaborative investigative efforts of state, local, and federal public health agencies indicate that romaine lettuce sold primarily at several locations of a single grocery store chain (Schnucks) was the likely source of illnesses in this outbreak. Contamination likely occurred before the product reached Schnucks locations.

Ill persons reported purchasing salads from salad bars at Schnucks between October 5 and October 24, 2011. A total of 9 locations of Schnucks were identified where more than one ill person reported purchasing a salad from the salad bar in the week before becoming ill. This included 2 separate locations where 4 ill persons reported purchasing a salad at each location. For locations where more than one ill person reported purchasing a salad from the salad bar and the date of purchase was known, dates of purchase were all within 4 days of other ill persons purchasing a salad at that same location. Romaine lettuce served on salad bars at all locations of Schnucks had come from a single lettuce processing facility via a single distributor. This indicates that contamination of romaine lettuce likely occurred before the product reached Schnucks locations.

The FDA and several state agencies conducted traceback investigations for romaine lettuce to try to identify the source of contamination. Traceback investigations focused on ill persons who had eaten at salad bars at several locations of Schnucks and ill persons at university campuses in Minnesota (1 ill person) and Missouri (2 ill persons). Traceback analysis determined that a single common lot of romaine lettuce harvested from Farm A was used to supply Schnucks locations as well as the university campus in Minnesota during the time of the illnesses. This lot was also provided to a distributor that supplied lettuce to the university campus in Missouri, but records were not sufficient to determine if this lot was sent to this university campus. Preliminary findings of investigation at Farm A did not identify the source of the contamination. Farm A was no longer in production during the time of the investigation.