Henry-Ford-HospitalOfficials with the Michigan Department of Health and Human Services and Henry Ford Hospital in Detroit, Michigan, are trying to unravel how 14 patients in the same hospital unit were sickened last week with Salmonella.

Seven of these people have been discharged, while the other seven remain in the hospital and are isolated from other patients “as an added safety precaution,” according to a Detroit TV station report aired Tuesday night.

Sources at the 802-bed hospital said the outbreak doesn’t appear to be food-related, but they aren’t yet sure.

“No new patients have been identified this week. There’s no evidence at this time that the illness is food related,” a hospital statement read.

“Salmonella can be transmitted basically by anything that enters your mouth, whether it’s a dirty hand, touching something that has Salmonella and touching your mouth, or food,” said Dr. Frank McGeorge, an emergency room physician affiliated with Henry Ford Hospital. “In a hospital setting, it could be just about anything, and that’s where the detective work happens and really has to take place.”