The McHenry County Department of Health closed an online survey seeking information from diners who ate at or ordered from the D.C. Cobb’s restaurant in McHenry last week.
The survey closed on Thursday morning, department spokeswoman Lindsey Salvatelli said.
Now, the health department is using that information received from patrons to determine the cause and “identify people with common symptoms and food items,” Salvatelli said.
She said the health department expects to release more information about the survey on Friday.
D.C. Cobb’s management fully cooperated with the investigation, Salvatelli said.
The outbreak was identified Tuesday after 13 people complained of becoming ill after eating at the establishment, according to the department of health.
It was the second report of food- or water-borne illness in recent weeks. It is not clear whether the cases are connected.
The McHenry County Department of Health identified eight cases of campylobacteriosis between Aug. 17 and Aug. 30, according to a news release earlier this month.
That number was four times more cases compared to the previous two weeks and three times the number of cases reported in the entire previous month.
Campylobacter bacteria is the most common cause of bacterial diarrhea in the U.S., health officials said. The bacteria can cause diarrhea, which may be bloody, as well as cramping, abdominal pain and fever two to five days after exposure. Nausea and vomiting may also occur, health department officials said.
“People can become ill with campylobacteriosis by eating contaminated food, drinking contaminated water or having contact with infected animals,” the release stated.
Precautions against campylobacteriosis include not drinking unpasteurized milk, water from lakes, rivers and ponds, practicing good hand hygiene, cooking raw meats to the proper internal temperature, and using soap and hot water on cutting boards, counters or utensils to prevent cross-contamination, the health department said.