A potentially deadly form of food poisoning may not always be caused by something you ate. Researchers from the Centers for Disease Control and Prevention report exposure to infected rodents may also cause salmonellosis.

The medical detective story began with the identification of a specific form of the infection in hamsters sent by a pet distributor in Minnesota to the University of Minnesota Veterinary Diagnostic Laboratory in St. Paul. Further investigation found many hamsters carried by the same distributor were suffering from an illness suggestive of salmonellosis, and researchers subsequently matched the exact bacterial strain to 28 patients who came down with the disease.

Researchers interviewed 22 of the "food-poisoning" victims, and 13 reported exposure to pet hamsters, mice, or rats. Six were hospitalized with the infection, which is especially serious because it is resistant to some drugs designed to treat it. The bacterial strain was subsequently cultured from the pet mouse of one patient and from seven hamsters found in pet stores.