Almost 300 people are said to have fallen ill from salmonella outbreak in the US linked to raw chicken from three plants owned by Foster Farms.

The US Department of Agriculture said strains of salmonella heidelberg are "associated" with products made at Foster Farms sites in California.

In a public health alert issued yesterday (7 October), the USDA's Food Safety and Inspection Service said there had been an estimated 278 illnesses "recently reported" in 18 states. Those who had fallen ill were "predominantly" in California, the FSIS said.

"The outbreak is continuing," the FSIS said. "The investigations indicate that consumption of Foster Farms brand chicken and other brand chicken produced at Foster Farms plants are the likely source of this outbreak of Salmonella Heidelberg infections. Illnesses were linked to Foster Farms brand chicken through epidemiologic, laboratory and traceback investigations conducted by local, state, and federal officials."

The agency said it was unable to link the illnesses to a specific product. However, it said raw products from the three sites under scrutiny bear three numbers: P6137, P6137A and P7632.

Foster Farms president Ron Foster said the family-owned company had "maintained an excellent food safety record" throughout its history.

"We deeply regret any foodborne illness that may be associated with any of our products. Food safety is at the very heart of our business," Mr Foster said. "It is a continuous process of improvement. In addition to collaborating with FSIS and the Centers for Disease Control and Prevention, the company has retained national experts in epidemiology and food safety technology to assess current practices and identify opportunities for further improvement."

The poultry processor said consumers raw poultry should be handled and cooked according to safe handline guidelines.

"Salmonella is naturally occurring in poultry and can be fully eradicated if raw product is properly handled and fully cooked," Dr. Robert O'Connor, Foster Farms' food safety chief and head veterinaria, said. "All poultry producers strive to reduce bacterial presence, including Salmonella. We take food safety very seriously. When the incidence of illnesses linked to Salmonella increased, we wanted to know why and we have worked quickly to identify and implement additional controls."

He added: "It is also important to reassure the public that the FSIS process has not been affected by the recent government shutdown."