SPRINGFIELD, Ill. (STMW) — The Centers for Disease Control says the salmonella outbreak involving Jimmy Johns alfalfa sprouts has now spread to 15 states including Illinois and has sickened 89 people.

C-D-C says Illinois has the most cases with 50 people sick.

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The Illinois Department of Public Health has added DuPage County to the list of locales where someone has eaten at a Jimmy John’s restaurant and tested positive for salmonella poisoning.

Previously, Cook, McHenry and Will counties had already been identified, along with several downstate counties.

Public Health spokeswoman Melaney Arnold said testing will continue over the holiday weekend, including possibly Christmas Day if needed.

“We are still going to have testing over the weekend,” Arnold said. “If it needs to be tested that day, it’ll be tested that day.”

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Samples are time-sensitive and could die if not tested in short order, Arnold said.

This week, local Jimmy John’s restaurants pulled sprouts from their sandwiches as a precautionary measure.

There have been 50 confirmed cases in Illinois so far, Arnold said.

Jimmy John’s stores and their sprouts providers have tested negative since the outbreak began.

Symptoms of salmonella include diarrhea, vomiting, fever and stomach cramps. The state says people who contract the illness should contact a doctor.

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