ATLANTA – A multistate outbreak of Salmonella Heidelberg infections linked to Foster Farms chicken products has grown to 389 cases in 23 states and Puerto Rico, the Atlanta-based Centers for Disease Control and Prevention reported. Seventy-four percent of the cases were reported in California.

Forty-percent of those infected by the pathogen were hospitalized, an unusually high hospitalization rate for an outbreak, according to CDC. The agency also noted that blood infections developed in 14 percent of people affected by the outbreak; CDC said approximately 5 percent of people infected with Salmonella develop blood infections.

The most recent illnesses were reported on Oct. 29, but CDC said there could be more cases not yet reported because of the time it takes between illness onsets and when the illness is reported. However, CDC data indicates that the outbreak is slowing.

Under threat of plant closures by the Food Safety and Inspection Service, Foster Farms implemented a number of food-safety interventions at three of its California processing plants that were linked to the outbreak. The company also refuted official claims about antibiotic-resistant strains of Salmonella in its chicken products.

Mexico banned imports of chicken from two Foster Farms facilities in Fresno, Calif. and another in Livingston, Calif., the first time Mexico has banned meat products from the US as a result of a public health alert issued by the Food Safety and Inspection Service. No recall notice was issued in the case, but some stores pulled Foster Farms products from shelves.