In early 2002, isolates of Salmonella Newport in New York state were found to be resistant to more than nine antibiotics and had a decreased susceptibility to the antibiotic, ceftriaxone. Since 1996, an increasing number of Salmonella Newport isolates had been found to be resistant to antibiotics. This particular strain was referred to as SN-MDR-AmpC. Subsequent to the discovery of cases in New York, four additional states discovered cases sharing the same strain of SN-MDR-AmpC. When the cases were investigated, it was found that consumption of undercooked ground beef was the only food that was significantly associated with a risk of infection. The risk of infection when undercooked ground beef was eaten was over 50 times greater than when well cooked meat was eaten. A sample of ground beef provided by a case-patient was analyzed and was found to be contaminated with SN-MDR-AmpC. Traceback of the meat implicated Emmpak Foods Inc., a subsidiary of Cargill, Inc. Most patients had eaten lean, or extra-lean, ground beef. This outbreak was the first to implicate ground beef as a source of SN-MDR-AmpC. It illustrated the spread of antibiotic resistance from animal products to humans.