The Orange County Register reports that a restaurant and the Orange County Health Department try to pinpoint origin of illness

The restaurant, a San Diego-based salad-bar chain, is cooperating with Orange County health officials who are trying to pinpoint the food that caused six children and one adult to get sick after eating at a Lake Forest restaurant.  Orange County health authorities confirmed that the diners tested positive for E. coli O157:H7, the same deadly strain that sickened hundreds of consumers in several other recent produce outbreaks that, starting last year, attracted national media attention.

Late Monday, the buffet-type restaurant and Orange County Health Care Agency officials said the seven customers ate at the Towne Center Drive restaurant from March 23 to March 25. Though the investigation is ongoing, the restaurant – in a retail center in the community of Foothill Ranch – remains open, the restaurant said. Through midday Tuesday, no other cases have been reported.

The seven people who contracted food poisoning are recovering, local health authorities said today. The group includes six children and a person in his or her 70s. Three of the ill people had to be hospitalized.

The illnesses tie another Orange County operation to a food poisoning outbreak. Last year, 71 customers of Irvine-based Taco Bell were sickened after they ate contaminated shredded lettuce. That outbreak was limited to several East Coast restaurants.  Orange County illnesses tied to the deadly E. coli strain identified in the outbreak are rare. Of the 702 local illnesses caused by pathogens and reported to health authorities in 2005, only eight cases were caused by E. coli O157:H7.