Updated 08/02/11 – 8:41 p.m.

WASHINGTON (CBS) — A salmonella outbreak involving ground turkey has hit Illinois and 25 other states. So far, 77 people have become ill, 7 of them in Illinois.

Officials say the cases have been reported in Cook, DuPage, Will and 4 downstate counties. So far, no brand names have been mentioned.

CBS 2’s Mike Parker went to a South Side restaurant that serves only turkey.

At the “Just Turkey” restaurant at 44th and Cottage Grove, the turkey burgers were sizzling on the grill, and the customers were lining up. They came not only for the ground turkey burgers but for the ground turkey tacos and turkey spaghetti.

The owners say that, like everyone else, they learned about the salmonella outbreak Tuesday afternoon.

“I was a little shocked … that hits right to the core of us,” said co-owner Greg Morton.

Greg and his brother and co-owner Brian Morton say they’ve checked with the suppliers of their Perdue brand ground turkey.

“Our food is safe,” said Brian. “They recommended everybody keep coming to us. We have no problems, no complaints.”

The Morton brothers say they always make sure that the turkey is properly cooked. That’s good news to Dr. Craig Conover with the Illinois Department of Public Health.

“You need to cook all meat thoroughly,” Conover said. “And turkey .. you can’t always tell by the color whether or not it’s cooked properly. You have to cook it to 165 degrees.”

Outside a South Loop supermarket, some shoppers, like Uniqua White were suddenly a little wary when they heard about the outbreak. White said she was a ground turkey eater, but when asked if she would buy some anytime soon, she answered “Not now. Not now that I know about that.”

Salmonella bacteria commonly causes diarrhea, fever and abdominal cramps. In older people and young children, the illness can be serious and require hospitalization.

LISTEN: Newsradio 780’s Regine Schlesinger reports

Health officials continue to try to locate the source. The U.S. Department of Agriculture has not yet issued a recall, saying inspectors are still trying to determine who produced the apparently contaminated ground turkey.

If you’re serving ground turkey, to be on the safe side, it must be cooked to a minimum of 165 degrees Fahrenheit on the inside. Use a meat thermometer to make sure.

You also need to make sure raw poultry does not come in contact with other foods and wash your hands thoroughly after handling raw turkey or other poultry.

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