North Carolina officials are investigating up to 21 possible cases of E. coli affecting people in six counties, with four children still hospitalized because of the ailment.
State Epidemiologist Megan Davies said Thursday that nine cases have been confirmed, and 12 more are being evaluated.
Most of the cases come from Wake County, which has seven confirmed and four suspected. Sampson County has six, and there is one each in Durham, Johnston, Franklin and Cleveland counties.
Eight of the nine confirmed cases occurred in people who attended the state fair, but Davies says investigators don't know yet how many of the suspected cases were at the event.
Davies says it's not clear yet what else the confirmed cases had in common besides attending the fair in its early days.