Foster Farms

The outbreak continues to vex Foster Farms, the largest poultry producer in California. (Justin Sullivan, Getty Images)

Dozens more people have been sickened by a salmonella outbreak tied to Foster Farms chicken that was thought to have been over, the Centers for Disease Control and Prevention said Monday.

The agency reported 51 new cases of Salmonella Heidelberg between mid-January and late February. Forty-four of the new cases were found in California.

“It raises concern that this outbreak may not be over,” said Robert Tauxe, the CDC's deputy director for the division of food-borne, waterborne and environmental diseases.

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That's a reversal from Jan. 16, the last time the CDC released an update on the outbreak. Officials then saw new cases dwindling, suggesting the outbreak was finished.

But with the latest cases, a total of 481 people have now been sickened nationwide since March, 2013. Patients range in age from less than 1 years old to 93 years old.

The outbreak continues to vex Foster Farms, the largest poultry producer in California, which is headquartered 25 miles southeast of Modesto in the rural community of Livingston.

The company’s trouble started last October when the U.S. Department of Agriculture issued a health alert warning consumers of salmonella linked to three Foster Farms processing facilities in Central California.

Inspectors subsequently threatened to suspend operations at the plants after discovering poor sanitary conditions that could have contributed to the outbreak.

Even as national retail chains like Kroger Co. pulled Foster Farms from its meat cases, the 75-year-old poultry firm never issued a recall. Instead, the company echoed the recommendations of federal inspectors, which was to cook all chicken to a minimum of 165 degrees Fahrenheit.

Foster Farms also issued a public apology, overhauled some of its safety practices and vowed to win back the trust of consumers. But in another setback, the firm closed its flagship factory in Livingston for 10 days in January because of a cockroach infestation.

The Foster Farms outbreak reignited a national debate among food safety and consumer advocates for federal laws to treat salmonella as strictly as other food-borne illnesses like E. coli, which triggers an automatic recall.

Salmonella is considered a common bacteria found regulalry in poultry. Because it can be killed through cooking, government regulators allow some levels of the contaminant. But the bug is a growing concern for the industry, partly because strains are becoming increasingly resistant to antibiotics.

The CDC said the strains of Salmonella Heidelberg linked to the current outbreak have shown resistance to commonly prescribed antibiotics. However,  those drugs aren’t typically used to treat salmonella infections, which can cause diarrhea, fever, and abdominal cramps.

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