An E. coli outbreak linked to ground beef has expanded to 10 states and has caused at least 156 people to fall ill, federal officials said Tuesday.

“Traceback investigations are ongoing to determine the source of raw ground beef supplied to grocery stores and restaurant locations where ill people reported eating,” the Centers for Disease Control and Prevention said.

So far 20 people have been hospitalized because of the outbreak, which began in early March, but no deaths have been reported.

The federal agency said the majority of cases have been reported in Kentucky, where 65 people have fallen ill, followed by Tennessee with 41 cases and Georgia with 33 cases. The other states include Florida, Illinois, Indiana, Minnesota, Mississippi, Ohio, and Virginia.

Georgia meat producer K2D Foods recently announced it is recalling over 100,000 pounds of ground beef in response to the outbreak.

Officials said they expect the number of people reported to be ill to rise.

“Illnesses that occurred after March 26, 2019, might not yet be reported due to the time it takes between when a person becomes ill with E. coli and when the illness is reported. This takes an average of two to three weeks,” the agency said.

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