Ten Minnesota residents not yet included in the national case count have E. coli O157:H7 infections from romaine lettuce, state officials said Tuesday. Following the May 6 report on one case in North Dakota, also not yet included in the national count, it appears the romaine outbreak continues to expand.

April 20 through May 2 were the illness onset dates for the Minnesota illnesses, according to the statement from the Minnesota Departments of Health (MDH), and Agriculture (MDA).

The Minnesota officials said the 10 confirmed cases “have been recently identified and linked to the multi-state outbreak.”

The cases are from both Minneapolis-St. Paul metro area and greater Minnesota counties; 90 percent are female. Three people have been hospitalized. Two developed hemolytic uremic syndrome (HUS), a potentially fatal complication that can include kidney failure and other severe problems.

All of the sick people in Minnesota who have been interviewed by public health investigators reported exposure to romaine lettuce. They said they ate romain from grocery stores, at restaurants and residential facilities. Both MDH and MDA are continuing to investigate.

The last national count on May 1 reported 121 confirmed cases and one death with 25 states included in the outbreak, according to the CDC. Fifty-two have required hospitalization. With North Dakota and Minnesota now reporting confirmed cases, there are 27 states involved in the outbreak.

“Do not eat, buy, or sell romaine lettuce unless you can confirm it is not from the Yuma growing region,” said Kirk Smith, manager of Minnesota’s Foodborne, Waterborne, Vectorborne, and Zoonotic Diseases section. “The Yuma growing region includes part of western Arizona and extends into the Imperial Valley of southeastern California, but does not include Salinas Valley or other growing regions in California.”

Romaine from the Yuma growing region should no longer be on sale; however, individuals should check their refrigerators for romaine lettuce grown earlier in season in the Yuma region.

Symptoms of illness caused by E. coli O157 typically include stomach cramps and diarrhea, often with bloody stools, but only a low-grade or no fever. People typically become ill two to five days after exposure, but this period can range from one to eight days. Most people recover in five to 10 days. However, E. coli O157 infections sometimes lead to HUS. Those most at risk of developing complications from E. coli O157 include children younger than 10, the elderly, and those with weakened immune systems.

Diarrhea associated with E. coli O157 infections should not be treated with antibiotics, as this practice might promote the development of HUS. Anyone who believes they may have developed an E. coli O157 infection should contact their healthcare provider.

Approximately 135 cases of E. coli O157 are reported each year in Minnesota.

The U.S. Food and Drug Administration and the CDC are running a federal investigation of the multi-state E. coli O157:H7 outbreak. CDC is expected to announce a new national count shortly.

The federal investigation with all the help it can muster from the impacted states still has not been able to pinpoint who grew and distributed pre-chopped romaine lettuce associated with the outbreak, which is approaching its ninth week.

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