At least 20 people in Wisconsin have E. coli infections that could be linked to an outbreak in Maryland that has been traced to ready-to-eat romaine lettuce salads. Some officials, however, say a specific cause  of the Wisconsin outbreak has not yet been determined.

In a Twitter post the head food safety official at the Food and Drug Administration, Frank Yiannas, urged the public to not consume any of the suspect salad. The agency is assisting with the outbreak investigation.

Ready Pac, the brand of the salads involved, is owned by Bonduelle Fresh Americas. Bonduelle posted a notice on its website that says government officials notified the company of only potential connections between E. coli patients in Maryland and the salads.

However, the Maryland Department of Health is reporting that “testing of unopened salad purchased by one of the patients identified the presence of E. coli O157 in the romaine lettuce. In addition to Sam’s Club, these salad bowls are distributed to many other retailers.”

The Ready Pac statement did not identify any specific retailers, rather stating the implicated product was shipped to “a club retailer in the state of Maryland.”

Neither the state nor the company reported how many pounds or packages of salad is involved. They also did not report what other companies may have purchased the implicated lettuce for additional products.

The Maryland health department notified the public that it is investigating a cluster of E. coli O157:H7 infections among seven patients in the state. All of the patients reported eating Ready Pac Bistro Bowl Chicken Caesar Salad purchased from various Sam’s Club locations in Maryland. There has been one hospitalization but no deaths associated with these cases.

Ready Pac officials say they tested the romaine in the fields but the company statement did not indicate whether the it does any testing during the processing and packaging processes. The statement also did not include any information about whether finished product testing is conducted.

The company did not issue a recall.

“We test all of our leafy greens — including romaine — in the fields prior to harvest, including screening for E. coli O157:H7. During this time frame, we did not have any positive test results for E. coli O157:H7. We are working in partnership with the Maryland Department of Health and are working as quickly as possible to identify the possible root cause to reduce potential impacts to consumers.

“Because the products identified are already significantly past their use-by dates, we are not taking any recall action, and it does not affect any product currently on store shelves. As always, please abide by any use-by dates, and do not consume any products that have exceeded these dates.”

In the outbreak in Wisconsin, the Department of Health Services reported three of the 20 patients in that state are children. Children’s immature immune systems mean they are more likely to develop serious complications from E. coli infections. 

Dr. Larry Lutwick, an infectious disease specialist with the Mayo Clinic in Eau Claire, WI, said he’s seen three cases of E. coli at his facility and believes they may be linked to the outbreak. He thinks his patients could have contracted the bacteria from lettuce.

“In two of the three cases they suspected it was from a salad or salad ingredient,” Lutwick said.

Lutwick added that E. coli has a long incubation period, which makes it difficult to investigate.

About E. coli infections

Anyone who has eaten any of the implicated product and developed symptoms of E. coli infection should seek medical attention and tell their doctor about their possible exposure to the bacteria. Specific tests are required to diagnose the infections, which can mimic other illnesses.

Most people with an E. coli O157 infection start feeling sick three to four days after eating or drinking something that contains the bacteria. However, illnesses can start anywhere from one to 10 days after exposure.

The symptoms of E. coli infections vary for each person but often include severe stomach cramps and diarrhea, which is often bloody. Some patients may also have a fever. Most patients recover within five to seven days. Others can develop severe or life-threatening symptoms and complications, according to the Centers for Disease Control and Prevention (CDC).

About 5 to 10 percent of those diagnosed with E. coli infections develop a potentially life-threatening kidney failure complication, known as a hemolytic uremic syndrome (HUS). Symptoms of HUS include fever, abdominal pain, feeling very tired, decreased frequency of urination, small unexplained bruises or bleeding, and pallor.

Many people with HUS recover within a few weeks, but some suffer permanent injuries or death. This condition can occur among people of any age but is most common in children younger than five years old because of their immature immune systems, older adults because of deteriorating immune systems, and people with compromised immune systems such as cancer patients.

Editor’s note originally posted Nov. 3: At this time, the credibility of the Food and Drug Administration (FDA) and the Centers for Disease Control and Prevention (CDC) is not to be trusted. Both agencies have shown a reckless disregard for the public’s right to know, and their reliability going forward remains suspect. For the next six weeks, Food Safety News will publish this note above on every story involving the FDA or CDC.

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