Illinois health officials investigating 26 cases of salmonella infections linked to ground beef

State and federal officials are investigating an outbreak of 26 cases of salmonella infections in northeastern Illinois linked to ground beef.

The source of the ground beef has not yet been identified, the Illinois Department of Public Health said Wednesday. The cases have been in Chicago and Cook, DuPage, Kane, Lake, McHenry and Will counties, with people falling ill between April 25 and May 18.

Some of the people who got sick said they ate undercooked ground beef. Public health officials are urging Illinois residents to use food thermometers when cooking ground beef, to make sure it reaches an internal temperature of 160°F.

The illness caused by salmonella can lead to diarrhea, stomach cramps and fever. People may also experience nausea, vomiting or a headache. If people experience those symptoms six to 72 hours after eating potentially contaminated beef, they should contact their health care providers and tell them they recently ate beef. Symptoms can last for four to seven days.

Children under 5, adults older than 65, people with compromised immune systems and people with certain heart and joint conditions may be more at risk for serious illness.

Public health officials are also urging people to follow food safety recommendations to avoid getting sick, including washing their hands, utensils and surfaces often; keeping raw meat and poultry away from food that won’t be cooked; and refrigerating perishable food within two hours or one hour if it’s exposed to temperatures above 90 degrees, such as in a car or at a picnic. Food should be thawed in a refrigerator, not on a counter.

The state is working with local health departments, the Centers for Disease Control and Prevention and the U.S. Department of Agriculture’s Food Safety and Inspection Service to identify additional infections, perform lab testing and find the source of the contaminated beef. State health departments and the CDC are also investigating a small number of cases in other states.