The federal Centers for Disease Control and Prevention (CDC) is working with the Illinois Department of Public Health (IDPH) and local health departments to investigate the Salmonella outbreak that has sickened at least 46 residents of Illinois since Nov. 1.

The CDC’s involvement could indicate the outbreak may extend beyond Illinois.

According to the IDPH, cultures from the 46 Illinois residents who became ill share a genetic match to a strain of Salmonella known as Serotype I 4,5,12,i-.  That strain–pronounced “four five twelve eye minus”–is noteworthy for its antibiotic resistance.

Many of the patients told health department investigators they had eaten alfalfa sprouts at Jimmy John’s sandwich outlets in nine Illinois counties–Adams, Champaign, Cook, Kankakee, McHenry, McLean, Peoria, Will and Winnebago.

The IDPH said it is investigating alfalfa sprout producers and suppliers and continues to test produce for Salmonella.  Officials ask consumers who may have eaten alfalfa sprouts and became ill with diarrhea and fever to see their physicians and contact their local health departments.

This is the second time in two years that Jimmy John’s has been linked to an outbreak involving alfalfa sprouts.  In 2008, college students in Colorado were among 14 sickened by E. coli after eating sandwiches garnished with contaminated sprouts at restaurants in two counties.