Kansas officials are investigating an E. coli outbreak among people who attended an annual festival at Louisburg Cider Mill, with the cause proving elusive after initial tests did not find the pathogen in the production area, finished cider or whole apples.

Seven people have been laboratory-confirmed with the outbreak strain of E. coli O157:H7, according to a statement issued Wednesday by the Kansas Department of Health and Environment (KDHE).

Josh Hebert, president of the 39-year-old operation, said the company is continuing to cooperate fully with state and federal officials. The KDHE and personnel from the U.S. Food and Drug Administration assessed the Louisburg Cider Mill on Oct. 27. State inspectors collected samples for testing.

Hebert said the Kansas Department of Agriculture notified him via email that all of the samples came back negative for E. coli.

The cider mill uses apples from growers in and around the Kansas City metropolitan area, Hebert said. The company uses a heat pasteurization process for all of its cider products but does not add preservatives.

During the annual Ciderfest, which was on the weekends of Sept. 24-25 and Oct. 1-2 this year, food and craft vendors have booths on the cider mill grounds. This year, Herbert said, there were 12 to 15 food vendors with everything from ice cream to barbecue. He was asked to provide a list of them to the state investigators.

The festival weekends also included pancake breakfasts by a local Lions Club this year.

In addition to those multiple food sources as possible vectors for the E. coli, a pony ride operation was on the mill grounds for the festival. A few goats, pigs and other farm animals are kept near the corn maze during the festival, but Herbert said it is not set up as a petting zoo.

State officials initially concentrated on activities during the first of the two festival weekends, Herbert said. But the notice posted Wednesday by the state health department references both weekends.

“If anyone has experienced diarrhea within one to 10 days after attending the Ciderfest on Sept. 24-25 or Oct. 1-2, please call the KDHE Epidemiology Hotline at 877-427-7317,” the health department notice requested.

The symptoms of E. coli O157:H7 infections vary for each person but often include severe stomach cramps, diarrhea that is often bloody and vomiting, according to the federal Centers for Disease Control and Prevention. If there is fever, it usually is not very high. Most people get better within a week. Some infections are very mild, but others are severe or even life-threatening.

As many as 10 percent of those who are diagnosed with E. coli infections develop a potentially life-threatening complication known as hemolytic uremic syndrome (HUS). Clues that a person is developing HUS include decreased frequency of urination, feeling very tired, and losing pink color in cheeks and inside the lower eyelids.

People with HUS should be hospitalized because their kidneys may stop working and they may develop other serious problems. Most persons with HUS recover within a few weeks, but some suffer permanent damage or die.

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