CHICAGO A salmonella outbreak linked to California-based poultry producer Foster Farms' contaminated chicken appears to be over, more than 17 months after it began, the Centers for Disease Control and Prevention said on Thursday.
The salmonella Heidelberg outbreak, which public health investigators say began on March 1, 2013, and ended July 11 this year, made 634 people sick in 29 states and Puerto Rico, the agency said.
Scientists identified seven strains of the bacteria in the outbreak, including some that were resistant to antibiotics used to treat humans for illnesses other than salmonella.
"Epidemiologic, laboratory and trace-back investigations conducted by local, state and federal officials indicated that consumption of Foster Farms brand chicken was the source of this outbreak of Salmonella Heidelberg infections," the CDC said in a statement.
No deaths were reported. Of the cases reported, 38 percent of the people were hospitalized - a higher rate than in a typical salmonella Heidelberg outbreak, investigators said.
For more than a year, the outbreak has roiled both the company and federal regulators in a public health controversy that put a critical spotlight on Foster Farms' food-safety practices. Critics also questioned USDA investigators' apparent struggles to connect the dots between extremely ill consumers and chicken produced by one of the nation's largest chicken companies.
Last year, the company said it began implementing a new $75 million food safety program to reduce salmonella contamination throughout the company, from farm to slaughterhouse.
"Foster Farms remains committed to continuing its progress and leading the industry in food safety," the company told Reuters in a statement.
Yet for much of the outbreak, the company publicly denied its chicken was to blame for making people sick. Proper cooking should have killed any salmonella on its meat, the company has said.
In early July, the company announced a limited recall of chicken produced at its three plants in central California. Now, according to the CDC, the U.S. Department of Agriculture's Food Safety and Inspection Service (FSIS) has determined that "measures undertaken by the firm to prevent salmonella contamination of raw chicken have been successful."
The news came on the same day the U.S. Department of Agriculture announced it will modernize its decades-old inspection methods for poultry, in an attempt to crack down on food-borne illness such as salmonella.
As part of this effort, the agency said, USDA's FSIS will require all poultry companies to take measures to prevent salmonella and campylobacter contamination, rather than addressing contamination after it occurs.
"The United States has been relying on a poultry inspection model that dates back to 1957 ... The system we are announcing today imposes stricter requirements on the poultry industry and places our trained inspectors where they can better ensure food is being processed safely," said USDA Secretary Tom Vilsack.