A surge in salmonella cases has prompted federal health officials to reverse their position that an outbreak tied to Foster Farms' California facilities is over, reopening questions about the safety of the company's operations.
The Centers for Disease Control and Prevention said in January that the outbreak - which began in March 2013 - had run its course. But the CDC now says that there were another 40 cases in February and 43 more since early March.
Most of the infections, including 34 of those reported since early March, occurred in California, federal officials said. So far no deaths have been reported.
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Since the outbreak began, 524 people have been infected by the bacterium known as Salmonella Heidelberg, 76 percent of them in California, according to the CDC. Normally the state sees about five cases a month.
Salmonella typically causes diarrhea, fever, or abdominal cramps. Of the cases for which the CDC has detailed information, 37 percent were hospitalized, which is considered higher than normal, said Matt Wise, who leads the outbreak response team in CDC's division of food borne, water borne and environmental diseases. Another 13 percent developed blood infections, according to the CDC, which said that typically that number is five percent.
This outbreak has been found to be resistant to certain antibiotics but it is unclear why, Wise said.
Health officials are unsure why there has been a renewed surge in cases in the past couple of months. The CDC, the US Department of Agriculture and the Food and Drug Administration are all investigating. The USDA said it will continue to take aggressive actions to prevent more illnesses, adding that its Food Safety and Inspection Service is working to make sure Foster Farms cooperates with the investigations.
Foster Farms said that it has already taken several steps at its three California plants -- two in Livington and one in Fresno -- in response to the salmonella outbreak.
"Since October 2013, Foster Farms has developed a multiple-hurdle approach to reduce or eliminate Salmonella at each stage of production – from screening breeder flocks before entering the Foster Farms system, to farms where the birds are raised, to the plants where the chicken is processed as a whole bird and when it is cut into parts," the company said in a statement.
"As a result, the company has steadily reduced the prevalence of Salmonella at the parts level toward a goal of less than 10 percent – well below the USDA- measured industry benchmark of 25 percent," Foster Farms said.
The USDA said it has not set a benchmark for poultry parts, adding that it plans to introduce such a standard in September. In 2012 the agency published a study that found the national average for chicken parts affected by salmonella was 25 percent.
Foster Farms acted after the US Department of Agriculture threatened to shut down its California facilities last October if the company did not develop a plan to address the outbreak.
In addition to its California plants, Foster Farms has chicken facilities in Kelso, Washington and Creswell, Oregon.