TRENTON (CBSNewYork) — Chopped romaine lettuce grown around Yuma, Arizona, is being blamed for the E. coli outbreak that sickened at least seven New Jersey residents and 35 people across 11 states last week.

The Center for Disease Control and Prevention said no specific grower, supplier, distributor, or brand has been identified.

The New Jersey Health Department was looking into eight cases of E. coli in four counties last week, with some citing a chain restaurant as a common link, but just the lettuce from the source appears to have been the cause.

Consumers who have bought romaine lettuce – including salads and salad mixes containing romaine lettuce – should not eat it and should throw it away, even if some of it was eaten and no one has gotten sick.

All restaurants and retailers are being advised by the CDC to ask their food suppliers about the source of their romaine lettuce and refrain from selling or servicing any that was grown in Yuma, Arizona.

“Individuals with this infection usually get better within about 5 to 7 days, however some illnesses can be serious or even life-threatening,” said New Jersey Health Commissioner Dr. Shereef Elnahal in a statement. “Anyone experiencing symptoms of this illness should see a healthcare provider.”

Symptoms vary from mild to severe diarrhea, abdominal cramps, nausea and vomiting.

“In many patients, symptoms don’t begin until three to four days after exposure to the toxin, which is produced by the E. coli,” Dr. Robert Glatter, an emergency room physician at Lenox Hill Hospital, told CBS2’s Alice Gainer. “This type of E. coli potentially could be dangerous. First of all, it produces a toxin. This toxin could actually lead to kidney failure and something called hemolytic uremic syndrome. It’s relatively rare, but if certain patients are immunocompromised, if they have cancer, if they have any other medical issues that put them at risk, then they could potentially have a bad outcome.”

Currently in New Jersey, the Department of Health has seven confirmed cases of E. Coli: 4 in Hunterdon County, and one each in Monmouth, Sussex and Somerset counties.

New York and Connecticut each have two cases, while Pennsylvania has nine.

More information about the outbreak is available on the CDC website or from the New Jersey Department of Health.