The U.S. Centers for Disease Control and Prevention (CDC) are investigating a mysterious outbreak of E. coli bacteria that has now spread across multiple state lines.

Unfortunately, the source of the outbreak remains unclear, and because of that, the CDC “is not recommending that consumers avoid any particular food at this time.” Until they can figure out just what is causing the mass food poisoning, “restaurants and retailers are not advised to avoid serving or selling any particular food. Both The U.S. Food and Drug Administration, and officials from the Department of Agriculture are assisting them in the investigation.

A total of 17 cases have been reported across Connecticut, Idaho, Missouri, New Jersey, Ohio, Pennsylvania, and Washington. Currently, scientists are matching the bacterial DNA in an attempt to link the cases and trace their origin. So far, six of the victims have been hospitalized, with only one developing severe complications — hemolytic uremic syndrome and kidney failure. Luckily, none of the patients have died.

“The investigation is still ongoing and a specific food item, grocery store, or restaurant chain has not been identified as the source of infections,” the CDC said. “State and local public health officials are interviewing ill people to determine what they ate and other exposures in the week before their illness started.”

As always, proper food cleaning and preparation is the best defense.