An antibiotic-resistant strain of salmonella is sickening people who eat contaminated beef and unpasteurized, soft Mexican cheese.
The U.S. Centers for Disease Control and Prevention reports the bacterial strain has already caused more than 250 Americans in 32 states to become ill.
Among that group, 60 people were hospitalized and two died.
Health officials say the so-called "Super Salmonella" strains are developed in animals and can be transmitted to humans.
CDC warns about new drug-resistant new strain of salmonella