In what is now the largest E. coli outbreak in Alabama in 20 years, 18 people who ate at Little Rosie’s restaurant in Huntsville, Alabama, have been confirmed as suffering from E. coli O157:H7 infections, and testing is being conducted to determine whether there are additional victims of the outbreak.

The Huntsville Times reports that two people remain hospitalized with hemolytic uremic syndrome, and a third hospitalized E. coli victim’s status was not available.

The newest confirmed victims are a 65-year-old man and a 43-year-old woman. Neither got sick enough to need hospital care.

Although state and county health officials point to shredded lettuce as the most likely culprit, Bill Marler, a Seattle lawyer who specializes in foodborne illness cases, said he suspects that the outbreak ultimately will be tied to ground beef.